diff --git a/onnxruntime/core/providers/cpu/controlflow/loop.cc b/onnxruntime/core/providers/cpu/controlflow/loop.cc
index c65dd2a04bf55..b33b1f189594b 100644
--- a/onnxruntime/core/providers/cpu/controlflow/loop.cc
+++ b/onnxruntime/core/providers/cpu/controlflow/loop.cc
@@ -244,7 +244,7 @@ static Status ConcatenateCpuOutput(void* /*stream*/,
 
   // we can't easily use a C++ template for the tensor element type,
   // so use a span for some protection but work in bytes
-  gsl::span<gsl::byte> output_span = gsl::make_span<gsl::byte>(static_cast<gsl::byte*>(output),
+  gsl::span<std::byte> output_span = gsl::make_span<std::byte>(static_cast<std::byte*>(output),
                                                                output_size_in_bytes);
 
   for (size_t i = 0, num_iterations = per_iteration_output.size(); i < num_iterations; ++i) {
@@ -257,7 +257,7 @@ static Status ConcatenateCpuOutput(void* /*stream*/,
                              " Expected:", per_iteration_shape, " Got:", iteration_data.Shape());
     }
 
-    auto src = gsl::make_span<const gsl::byte>(static_cast<const gsl::byte*>(iteration_data.DataRaw()),
+    auto src = gsl::make_span<const std::byte>(static_cast<const std::byte*>(iteration_data.DataRaw()),
                                                bytes_per_iteration);
     auto dst = output_span.subspan(i * bytes_per_iteration, bytes_per_iteration);
     gsl::copy(src, dst);
diff --git a/onnxruntime/core/providers/cuda/controlflow/loop.cc b/onnxruntime/core/providers/cuda/controlflow/loop.cc
index 3295b73a800c9..d66de7c74e647 100644
--- a/onnxruntime/core/providers/cuda/controlflow/loop.cc
+++ b/onnxruntime/core/providers/cuda/controlflow/loop.cc
@@ -84,10 +84,10 @@ static Status ConcatenateGpuOutput(void* stream, std::vector<OrtValue>& per_iter
     CUDA_RETURN_IF_ERROR(cudaMemcpyAsync(cur_output, iteration_data.DataRaw(), bytes_per_iteration,
                                          cudaMemcpyDeviceToDevice, static_cast<cudaStream_t>(stream)));
 
-    cur_output = static_cast<void*>((static_cast<gsl::byte*>(cur_output) + bytes_per_iteration));
+    cur_output = static_cast<void*>((static_cast<std::byte*>(cur_output) + bytes_per_iteration));
   }
 
-  ORT_ENFORCE(static_cast<gsl::byte*>(cur_output) - static_cast<gsl::byte*>(output) == output_size_in_bytes,
+  ORT_ENFORCE(static_cast<std::byte*>(cur_output) - static_cast<std::byte*>(output) == output_size_in_bytes,
               "Concatenation did not fill output buffer as expected.");
 
   return Status::OK();
diff --git a/onnxruntime/test/providers/base_tester.cc b/onnxruntime/test/providers/base_tester.cc
index 6bfe7bc3856ba..eecff3fa4d8ff 100644
--- a/onnxruntime/test/providers/base_tester.cc
+++ b/onnxruntime/test/providers/base_tester.cc
@@ -174,7 +174,7 @@ static std::unique_ptr<SparseTensor> MakeSparseTensor(MLDataType data_type, cons
   return p_tensor;
 }
 
-void BaseTester::CopyDataToTensor(gsl::span<const gsl::byte> data, Tensor& dst) {
+void BaseTester::CopyDataToTensor(gsl::span<const std::byte> data, Tensor& dst) {
   ORT_ENFORCE(dst.SizeInBytes() >= data.size_bytes(), "Not enough space in the destination tensor");
   memcpy(dst.MutableDataRaw(), data.data(), data.size_bytes());
 }
@@ -203,7 +203,7 @@ void BaseTester::AddSparseCooTensorData(std::vector<Data>& data,
                                         MLDataType data_type,
                                         const char* name,
                                         gsl::span<const int64_t> dims,
-                                        gsl::span<const gsl::byte> values,
+                                        gsl::span<const std::byte> values,
                                         gsl::span<const int64_t> indices,
                                         const ValidateOutputParams& check_params,
                                         const std::vector<std::string>* dim_params) {
@@ -247,7 +247,7 @@ void BaseTester::AddSparseCsrTensorData(std::vector<Data>& data,
                                         MLDataType data_type,
                                         const char* name,
                                         gsl::span<const int64_t> dims,
-                                        gsl::span<const gsl::byte> values,
+                                        gsl::span<const std::byte> values,
                                         gsl::span<const int64_t> inner_indices,
                                         gsl::span<const int64_t> outer_indices,
                                         const ValidateOutputParams& check_params,
diff --git a/onnxruntime/test/providers/base_tester.h b/onnxruntime/test/providers/base_tester.h
index 512b3402c5986..d39cc3c750dec 100644
--- a/onnxruntime/test/providers/base_tester.h
+++ b/onnxruntime/test/providers/base_tester.h
@@ -868,7 +868,7 @@ class BaseTester {
   void AddShapeToTensorData(NodeArg& node_arg, gsl::span<const int64_t> dims,
                             const std::vector<std::string>* dim_params);
 
-  void CopyDataToTensor(gsl::span<const gsl::byte> data, Tensor& dst);
+  void CopyDataToTensor(gsl::span<const std::byte> data, Tensor& dst);
 
 #if !defined(DISABLE_SPARSE_TENSORS)
   NodeArg MakeSparseNodeArg(int32_t dtype, const char* name,
@@ -879,7 +879,7 @@ class BaseTester {
                               MLDataType data_type,
                               const char* name,
                               gsl::span<const int64_t> dims,
-                              gsl::span<const gsl::byte> values,
+                              gsl::span<const std::byte> values,
                               gsl::span<const int64_t> indices,
                               const ValidateOutputParams& check_params,
                               const std::vector<std::string>* dim_params = nullptr);
@@ -895,7 +895,7 @@ class BaseTester {
                               MLDataType data_type,
                               const char* name,
                               gsl::span<const int64_t> dims,
-                              gsl::span<const gsl::byte> values,
+                              gsl::span<const std::byte> values,
                               gsl::span<const int64_t> inner_indices,
                               gsl::span<const int64_t> outer_indices,
                               const ValidateOutputParams& check_params,