diff --git a/PuferFishContracts/PuferFishContracts/DataModels/BuyerDataModel.cs b/PuferFishContracts/PuferFishContracts/DataModels/BuyerDataModel.cs
index 3b61284..6f328fa 100644
--- a/PuferFishContracts/PuferFishContracts/DataModels/BuyerDataModel.cs
+++ b/PuferFishContracts/PuferFishContracts/DataModels/BuyerDataModel.cs
@@ -28,6 +28,9 @@ namespace PuferFishContracts.DataModels
             if (FIO.IsEmpty())
                 throw new ValidationException("Field FIO is empty");
 
+            if (!Regex.IsMatch(FIO, @"\b[А-ЯЁ][а-яё]*\b \b[А-ЯЁ][а-яё]*\b \b[А-ЯЁ][а-яё]*\b"))
+                throw new ValidationException("Field FIO is not a FIO");
+
             if (PhoneNumber.IsEmpty())
                 throw new ValidationException("Field PhoneNumber is empty");
 
diff --git a/PuferFishContracts/PuferFishContracts/DataModels/WorkerDataModel.cs b/PuferFishContracts/PuferFishContracts/DataModels/WorkerDataModel.cs
index 639515f..e1ea449 100644
--- a/PuferFishContracts/PuferFishContracts/DataModels/WorkerDataModel.cs
+++ b/PuferFishContracts/PuferFishContracts/DataModels/WorkerDataModel.cs
@@ -8,6 +8,7 @@ using PuferFishContracts.Exceptions;
 using System.Xml;
 using PuferFishContracts.Infrastructure;
 using static System.Runtime.InteropServices.JavaScript.JSType;
+using System.Text.RegularExpressions;
 
 namespace PuferFishContracts.DataModels;
 
@@ -23,16 +24,25 @@ public class WorkerDataModel(string id, string fio, string postId, DateTime birt
     {
         if (Id.IsEmpty())
             throw new ValidationException("Field Id is empty");
+
         if (!Id.IsGuid())
             throw new ValidationException("The value in the field Id is not a unique identifier");
+
         if (FIO.IsEmpty())
             throw new ValidationException("Field FIO is empty");
+
+        if (!Regex.IsMatch(FIO, @"\b[А-ЯЁ][а-яё]*\b \b[А-ЯЁ][а-яё]*\b \b[А-ЯЁ][а-яё]*\b"))
+            throw new ValidationException("Field FIO is not a FIO");
+
         if (PostId.IsEmpty())
             throw new ValidationException("Field PostId is empty");
+
         if (!PostId.IsGuid())
             throw new ValidationException("The value in the field PostId is not a unique identifier");
+
         if (BirthDate.Date > DateTime.Now.AddYears(-16).Date)
             throw new ValidationException($"Minors cannot be hired (BirthDate = { BirthDate.ToShortDateString() })");
+
         if (EmploymentDate.Date < BirthDate.Date)
             throw new ValidationException("The date of employment cannot be less than the date of birth");
         if ((EmploymentDate - BirthDate).TotalDays / 365 < 16) //EmploymentDate.Year - BirthDate.Year
diff --git a/PuferFishContracts/PuferFishTests/DataModelsTests/BuyerDataModelTests.cs b/PuferFishContracts/PuferFishTests/DataModelsTests/BuyerDataModelTests.cs
index ab09bba..fedfb77 100644
--- a/PuferFishContracts/PuferFishTests/DataModelsTests/BuyerDataModelTests.cs
+++ b/PuferFishContracts/PuferFishTests/DataModelsTests/BuyerDataModelTests.cs
@@ -14,17 +14,17 @@ namespace PuferFishTests.DataModelsTests
         [Test]
         public void IdIsNullOrEmptyTest()
         {
-            var buyer = CreateDataModel(null, "fio", "number", 10);
+            var buyer = CreateDataModel(null, "Фамилия Имя Отчество", "number", 10);
             Assert.That(() => buyer.Validate(),
             Throws.TypeOf<ValidationException>());
-            buyer = CreateDataModel(string.Empty, "fio", "number", 10);
+            buyer = CreateDataModel(string.Empty, "Фамилия Имя Отчество", "number", 10);
             Assert.That(() => buyer.Validate(),
             Throws.TypeOf<ValidationException>());
         }
         [Test]
         public void IdIsNotGuidTest()
         {
-            var buyer = CreateDataModel("id", "fio", "number", 10);
+            var buyer = CreateDataModel("id", "Фамилия Имя Отчество", "number", 10);
             Assert.That(() => buyer.Validate(),
             Throws.TypeOf<ValidationException>());
         }
@@ -43,11 +43,11 @@ namespace PuferFishTests.DataModelsTests
         [Test]
         public void PhoneNumberIsNullOrEmptyTest()
         {
-            var buyer = CreateDataModel(Guid.NewGuid().ToString(), "fio", null,
+            var buyer = CreateDataModel(Guid.NewGuid().ToString(), "Фамилия Имя Отчество", null,
             10);
             Assert.That(() => buyer.Validate(),
             Throws.TypeOf<ValidationException>());
-            buyer = CreateDataModel(Guid.NewGuid().ToString(), "fio",
+            buyer = CreateDataModel(Guid.NewGuid().ToString(), "Фамилия Имя Отчество",
             string.Empty, 10);
             Assert.That(() => buyer.Validate(),
             Throws.TypeOf<ValidationException>());
@@ -55,7 +55,7 @@ namespace PuferFishTests.DataModelsTests
         [Test]
         public void PhoneNumberIsIncorrectTest()
         {
-            var buyer = CreateDataModel(Guid.NewGuid().ToString(), "fio", "777",
+            var buyer = CreateDataModel(Guid.NewGuid().ToString(), "Фамилия Имя Отчество", "777",
             10);
             Assert.That(() => buyer.Validate(),
             Throws.TypeOf<ValidationException>());
@@ -64,7 +64,7 @@ namespace PuferFishTests.DataModelsTests
         public void AllFieldsIsCorrectTest()
         {
             var buyerId = Guid.NewGuid().ToString();
-            var fio = "Fio";
+            var fio = "Фамилия Имя Отчество";
             var phoneNumber = "+7-777-777-77-77";
             var points = 11;
             var buyer = CreateDataModel(buyerId, fio, phoneNumber, points);
diff --git a/PuferFishContracts/PuferFishTests/DataModelsTests/WorkerDataModelTests.cs b/PuferFishContracts/PuferFishTests/DataModelsTests/WorkerDataModelTests.cs
index 3524e04..1562aed 100644
--- a/PuferFishContracts/PuferFishTests/DataModelsTests/WorkerDataModelTests.cs
+++ b/PuferFishContracts/PuferFishTests/DataModelsTests/WorkerDataModelTests.cs
@@ -15,11 +15,11 @@ internal class WorkerDataModelTests
     [Test]
     public void IdIsNullOrEmptyTest()
     {
-        var worker = CreateDataModel(null, "fio", Guid.NewGuid().ToString(),
+        var worker = CreateDataModel(null, "Фамилия Имя Отчество", Guid.NewGuid().ToString(),
         DateTime.Now.AddYears(-18), DateTime.Now, false);
         Assert.That(() => worker.Validate(),
         Throws.TypeOf<ValidationException>());
-        worker = CreateDataModel(string.Empty, "fio",
+        worker = CreateDataModel(string.Empty, "Фамилия Имя Отчество",
         Guid.NewGuid().ToString(), DateTime.Now.AddYears(-18), DateTime.Now, false);
         Assert.That(() => worker.Validate(),
         Throws.TypeOf<ValidationException>());
@@ -27,7 +27,7 @@ internal class WorkerDataModelTests
     [Test]
     public void IdIsNotGuidTest()
     {
-        var worker = CreateDataModel("id", "fio", Guid.NewGuid().ToString(),
+        var worker = CreateDataModel("id", "Фамилия Имя Отчество", Guid.NewGuid().ToString(),
         DateTime.Now.AddYears(-18), DateTime.Now, false);
         Assert.That(() => worker.Validate(),
         Throws.TypeOf<ValidationException>());
@@ -47,11 +47,11 @@ internal class WorkerDataModelTests
     [Test]
     public void PostIdIsNullOrEmptyTest()
     {
-        var worker = CreateDataModel(Guid.NewGuid().ToString(), "fio", null,
+        var worker = CreateDataModel(Guid.NewGuid().ToString(), "Фамилия Имя Отчество", null,
         DateTime.Now.AddYears(-18), DateTime.Now, false);
         Assert.That(() => worker.Validate(),
         Throws.TypeOf<ValidationException>());
-        worker = CreateDataModel(Guid.NewGuid().ToString(), "fio",
+        worker = CreateDataModel(Guid.NewGuid().ToString(), "Фамилия Имя Отчество",
         string.Empty, DateTime.Now.AddYears(-18), DateTime.Now, false);
         Assert.That(() => worker.Validate(),
         Throws.TypeOf<ValidationException>());
@@ -59,7 +59,7 @@ internal class WorkerDataModelTests
     [Test]
     public void PostIdIsNotGuidTest()
     {
-        var worker = CreateDataModel(Guid.NewGuid().ToString(), "fio",
+        var worker = CreateDataModel(Guid.NewGuid().ToString(), "Фамилия Имя Отчество",
 "postId", DateTime.Now.AddYears(-18), DateTime.Now, false);
         Assert.That(() => worker.Validate(),
         Throws.TypeOf<ValidationException>());
@@ -67,7 +67,7 @@ internal class WorkerDataModelTests
     [Test]
     public void BirthDateIsNotCorrectTest()
     {
-        var worker = CreateDataModel(Guid.NewGuid().ToString(), "fio",
+        var worker = CreateDataModel(Guid.NewGuid().ToString(), "Фамилия Имя Отчество",
         Guid.NewGuid().ToString(), DateTime.Now.AddYears(-16).AddDays(1), DateTime.Now,
         false);
         Assert.That(() => worker.Validate(),
@@ -76,12 +76,12 @@ internal class WorkerDataModelTests
     [Test]
     public void BirthDateAndEmploymentDateIsNotCorrectTest()
     {
-        var worker = CreateDataModel(Guid.NewGuid().ToString(), "fio",
+        var worker = CreateDataModel(Guid.NewGuid().ToString(), "Фамилия Имя Отчество",
         Guid.NewGuid().ToString(), DateTime.Now.AddYears(-18), DateTime.Now.AddYears(-
         18).AddDays(-1), false);
         Assert.That(() => worker.Validate(),
         Throws.TypeOf<ValidationException>());
-        worker = CreateDataModel(Guid.NewGuid().ToString(), "fio",
+        worker = CreateDataModel(Guid.NewGuid().ToString(), "Фамилия Имя Отчество",
         Guid.NewGuid().ToString(), DateTime.Now.AddYears(-18), DateTime.Now.AddYears(-
         16), false);
         Assert.That(() => worker.Validate(),
@@ -91,7 +91,7 @@ internal class WorkerDataModelTests
     public void AllFieldsIsCorrectTest()
     {
         var workerId = Guid.NewGuid().ToString();
-        var fio = "fio";
+        var fio = "Фамилия Имя Отчество";
         var postId = Guid.NewGuid().ToString();
         var birthDate = DateTime.Now.AddYears(-16).AddDays(-1);
         var employmentDate = DateTime.Now;