diff --git a/arm_compute/core/Utils.h b/arm_compute/core/Utils.h
index ab5d110..06d6746 100644
--- a/arm_compute/core/Utils.h
+++ b/arm_compute/core/Utils.h
@@ -35,6 +35,7 @@
 #include <string>
 #include <type_traits>
 #include <utility>
+#include <vector>
 
 namespace arm_compute
 {
@@ -419,6 +420,37 @@
     return std::max(1, std::abs(std::accumulate(matrix, matrix + size, 0)));
 }
 
+/** Calculate the output shapes of the depth concatenate function.
+ *
+ * @param[in] inputs_vector The vector that stores all the pointers to input.
+ *
+ * @return the output shape
+ */
+template <typename T>
+TensorShape calculate_depth_concatenate_shape(const std::vector<T *> &inputs_vector)
+{
+    TensorShape out_shape = inputs_vector[0]->info()->tensor_shape();
+
+    size_t max_x = 0;
+    size_t max_y = 0;
+    size_t depth = 0;
+
+    for(const auto &tensor : inputs_vector)
+    {
+        ARM_COMPUTE_ERROR_ON(tensor == nullptr);
+        const TensorShape shape = tensor->info()->tensor_shape();
+        max_x                   = std::max(shape.x(), max_x);
+        max_y                   = std::max(shape.y(), max_y);
+        depth += shape.z();
+    }
+
+    out_shape.set(0, max_x);
+    out_shape.set(1, max_y);
+    out_shape.set(2, depth);
+
+    return out_shape;
+}
+
 /** Calculate accurary required by the horizontal and vertical convolution computations
  *
  * @param[in] conv_col Pointer to the vertical vector of the separated convolution filter
diff --git a/src/runtime/CL/functions/CLDepthConcatenate.cpp b/src/runtime/CL/functions/CLDepthConcatenate.cpp
index f42627f..89e44ca 100644
--- a/src/runtime/CL/functions/CLDepthConcatenate.cpp
+++ b/src/runtime/CL/functions/CLDepthConcatenate.cpp
@@ -25,6 +25,7 @@
 
 #include "arm_compute/core/CL/ICLTensor.h"
 #include "arm_compute/core/Error.h"
+#include "arm_compute/core/Helpers.h"
 #include "arm_compute/core/PixelValue.h"
 #include "arm_compute/core/Types.h"
 #include "arm_compute/runtime/CL/CLScheduler.h"
@@ -51,6 +52,11 @@
     _concat_kernels_vector  = arm_compute::support::cpp14::make_unique<CLDepthConcatenateKernel[]>(_num_inputs);
     _border_handlers_vector = arm_compute::support::cpp14::make_unique<CLFillBorderKernel[]>(_num_inputs);
 
+    TensorShape output_shape = calculate_depth_concatenate_shape(inputs_vector);
+
+    // Output auto inizialitation if not yet initialized
+    auto_init_if_empty(*output->info(), output_shape, 1, inputs_vector[0]->info()->data_type(), inputs_vector[0]->info()->fixed_point_position());
+
     for(unsigned int i = 0; i < _num_inputs; i++)
     {
         _concat_kernels_vector[i].configure(inputs_vector.at(i), depth_offset, output);
diff --git a/src/runtime/NEON/functions/NEDepthConcatenate.cpp b/src/runtime/NEON/functions/NEDepthConcatenate.cpp
index 90eee4f4..f8ad2ab 100644
--- a/src/runtime/NEON/functions/NEDepthConcatenate.cpp
+++ b/src/runtime/NEON/functions/NEDepthConcatenate.cpp
@@ -24,6 +24,7 @@
 #include "arm_compute/runtime/NEON/functions/NEDepthConcatenate.h"
 
 #include "arm_compute/core/Error.h"
+#include "arm_compute/core/Helpers.h"
 #include "arm_compute/core/ITensor.h"
 #include "arm_compute/core/PixelValue.h"
 #include "arm_compute/core/Types.h"
@@ -48,6 +49,11 @@
     _concat_kernels_vector  = arm_compute::support::cpp14::make_unique<NEDepthConcatenateKernel[]>(_num_inputs);
     _border_handlers_vector = arm_compute::support::cpp14::make_unique<NEFillBorderKernel[]>(_num_inputs);
 
+    TensorShape output_shape = calculate_depth_concatenate_shape(inputs_vector);
+
+    // Output auto inizialitation if not yet initialized
+    auto_init_if_empty(*output->info(), output_shape, 1, inputs_vector[0]->info()->data_type(), inputs_vector[0]->info()->fixed_point_position());
+
     unsigned int depth_offset = 0;
     for(unsigned int i = 0; i < _num_inputs; ++i)
     {