diff --git a/src/OData.QueryBuilder/Conventions/Functions/IODataStringAndCollectionFunction.cs b/src/OData.QueryBuilder/Conventions/Functions/IODataStringAndCollectionFunction.cs
index 66612978..ac0058db 100644
--- a/src/OData.QueryBuilder/Conventions/Functions/IODataStringAndCollectionFunction.cs
+++ b/src/OData.QueryBuilder/Conventions/Functions/IODataStringAndCollectionFunction.cs
@@ -32,5 +32,10 @@ public interface IODataStringAndCollectionFunction
         /// http://docs.oasis-open.org/odata/odata/v4.01/odata-v4.01-part2-url-conventions.html#sec_concat
         /// </summary>
         string Concat(string s1, string s2);
+
+        /// <summary>
+        /// http://docs.oasis-open.org/odata/odata/v4.01/odata-v4.01-part2-url-conventions.html#sec_indexof
+        /// </summary>
+        int IndexOf(string columnName, string value);
     }
 }
diff --git a/src/OData.QueryBuilder/Expressions/Visitors/ODataOptionFilterExpressionVisitor.cs b/src/OData.QueryBuilder/Expressions/Visitors/ODataOptionFilterExpressionVisitor.cs
index fd12e209..0618362b 100644
--- a/src/OData.QueryBuilder/Expressions/Visitors/ODataOptionFilterExpressionVisitor.cs
+++ b/src/OData.QueryBuilder/Expressions/Visitors/ODataOptionFilterExpressionVisitor.cs
@@ -138,6 +138,11 @@ protected override string VisitMethodCallExpression(MethodCallExpression methodC
                     var toLower0 = VisitExpression(methodCallExpression.Arguments[0]);
 
                     return $"{nameof(IODataFunction.ToLower).ToLowerInvariant()}({toLower0})";
+                case nameof(IODataStringAndCollectionFunction.IndexOf):
+                    var indexOf0 = VisitExpression(methodCallExpression.Arguments[0]);
+                    var indexOf1 = VisitExpression(methodCallExpression.Arguments[1]);
+
+                    return $"{nameof(IODataFunction.IndexOf).ToLowerInvariant()}({indexOf0},{indexOf1})";
                 case nameof(IConvertFunction.ConvertEnumToString):
                     return $"'{_valueExpression.GetValue(methodCallExpression.Arguments[0])}'";
                 case nameof(IConvertFunction.ConvertDateTimeToString):
diff --git a/test/OData.QueryBuilder.Test/ODataQueryOptionListTest.cs b/test/OData.QueryBuilder.Test/ODataQueryOptionListTest.cs
index 2c374ee8..5323d810 100644
--- a/test/OData.QueryBuilder.Test/ODataQueryOptionListTest.cs
+++ b/test/OData.QueryBuilder.Test/ODataQueryOptionListTest.cs
@@ -1090,9 +1090,21 @@ public void ODataQueryBuilderList_Filter_Method_Not_Supported_NotSupportedExcept
                 .Invoking(c => c
                     .For<ODataTypeEntity>(s => s.ODataType)
                     .ByList()
-                    .Filter((s, f) => @string.IndexOf("t") == 1)
+                    .Filter((s, f) => @string.Trim() == "s")
                     .ToUri())
-                .Should().Throw<NotSupportedException>().WithMessage($"Method {nameof(string.IndexOf)} not supported");
+                .Should().Throw<NotSupportedException>().WithMessage($"Method {nameof(string.Trim)} not supported");
+        }
+
+        [Fact(DisplayName = "IndexOf Test => Success")]
+        public void ODataQueryBuilderList_Test_IndexOf()
+        {
+            var uri = _odataQueryBuilderDefault
+                .For<ODataTypeEntity>(s => s.ODataType)
+                .ByList()
+                .Filter((s, f) => f.IndexOf(s.ODataKind.ODataCode.Code, "testCode") == 1)
+                .ToUri();
+
+            uri.OriginalString.Should().Be("http://mock/odata/ODataType?$filter=indexof(ODataKind/ODataCode/Code,'testCode') eq 1");
         }
     }
 }