diff --git a/src/Services/Ordering/Ordering.API/Application/Validations/CompleteOrderCommandValidator.cs b/src/Services/Ordering/Ordering.API/Application/Validations/CompleteOrderCommandValidator.cs
new file mode 100644
index 000000000..31ba48d68
--- /dev/null
+++ b/src/Services/Ordering/Ordering.API/Application/Validations/CompleteOrderCommandValidator.cs
@@ -0,0 +1,11 @@
+namespace Microsoft.eShopOnContainers.Services.Ordering.API.Application.Validations;
+
+public class CompleteOrderCommandValidator : AbstractValidator<CompleteOrderCommand>
+{
+    public CompleteOrderCommandValidator(ILogger<CompleteOrderCommandValidator> logger)
+    {
+        RuleFor(order => order.OrderNumber).NotEmpty().WithMessage("No orderId found");
+
+        logger.LogTrace("INSTANCE CREATED - {ClassName}", GetType().Name);
+    }
+}
diff --git a/src/Services/Ordering/Ordering.API/Program.cs b/src/Services/Ordering/Ordering.API/Program.cs
index 56d76de33..cab0e0b95 100644
--- a/src/Services/Ordering/Ordering.API/Program.cs
+++ b/src/Services/Ordering/Ordering.API/Program.cs
@@ -23,6 +23,7 @@ services.AddMediatR(cfg =>
 
 // Register the command validators for the validator behavior (validators based on FluentValidation library)
 services.AddSingleton<IValidator<CancelOrderCommand>, CancelOrderCommandValidator>();
+services.AddSingleton<IValidator<CompleteOrderCommand>, CompleteOrderCommandValidator>();
 services.AddSingleton<IValidator<CreateOrderCommand>, CreateOrderCommandValidator>();
 services.AddSingleton<IValidator<IdentifiedCommand<CreateOrderCommand, bool>>, IdentifiedCommandValidator>();
 services.AddSingleton<IValidator<ShipOrderCommand>, ShipOrderCommandValidator>();