diff --git a/src/libslic3r/GCode.cpp b/src/libslic3r/GCode.cpp
index ba2e19bfa..4fb3637b1 100644
--- a/src/libslic3r/GCode.cpp
+++ b/src/libslic3r/GCode.cpp
@@ -1482,7 +1482,7 @@ void GCode::_do_export(Print& print, GCodeOutputStream &file, ThumbnailsGenerato
     //BBS: total estimated printing time
     file.write_format(";%s\n", GCodeProcessor::reserved_tag(GCodeProcessor::ETags::Estimated_Printing_Time_Placeholder).c_str());
     //BBS: total layer number
-    file.write_format("; total layer number: %d\n", m_layer_count);
+    file.write_format(";%s\n", GCodeProcessor::reserved_tag(GCodeProcessor::ETags::Total_Layer_Number_Placeholder).c_str());
     file.write_format("; HEADER_BLOCK_END\n\n");
 
     //BBS: write global config at the beginning of gcode file because printer need these config information
diff --git a/src/libslic3r/GCode/GCodeProcessor.cpp b/src/libslic3r/GCode/GCodeProcessor.cpp
index 40912dcc3..22be036ae 100644
--- a/src/libslic3r/GCode/GCodeProcessor.cpp
+++ b/src/libslic3r/GCode/GCodeProcessor.cpp
@@ -54,7 +54,8 @@ const std::vector<std::string> GCodeProcessor::Reserved_Tags = {
     " CUSTOM_GCODE",
     "_GP_FIRST_LINE_M73_PLACEHOLDER",
     "_GP_LAST_LINE_M73_PLACEHOLDER",
-    "_GP_ESTIMATED_PRINTING_TIME_PLACEHOLDER"
+    "_GP_ESTIMATED_PRINTING_TIME_PLACEHOLDER",
+    "_GP_TOTAL_LAYER_NUMBER_PLACEHOLDER"
 };
 
 const std::string GCodeProcessor::Flush_Start_Tag = " FLUSH_START";
@@ -358,7 +359,7 @@ void GCodeProcessor::TimeProcessor::reset()
     machines[static_cast<size_t>(PrintEstimatedStatistics::ETimeMode::Normal)].enabled = true;
 }
 
-void GCodeProcessor::TimeProcessor::post_process(const std::string& filename, std::vector<GCodeProcessorResult::MoveVertex>& moves, std::vector<size_t>& lines_ends)
+void GCodeProcessor::TimeProcessor::post_process(const std::string& filename, std::vector<GCodeProcessorResult::MoveVertex>& moves, std::vector<size_t>& lines_ends, size_t total_layer_num)
 {
     FilePtr in{ boost::nowide::fopen(filename.c_str(), "rb") };
     if (in.f == nullptr)
@@ -470,6 +471,12 @@ void GCodeProcessor::TimeProcessor::post_process(const std::string& filename, st
                     }
                 }
             }
+            //BBS: write total layer number
+            else if (line == reserved_tag(ETags::Total_Layer_Number_Placeholder)) {
+                char buf[128];
+                sprintf(buf, "; total layer number: %zd\n", total_layer_num);
+                ret += buf;
+            }
         }
 
         if (! ret.empty())
@@ -1424,7 +1431,7 @@ void GCodeProcessor::finalize(bool post_process)
 #endif // ENABLE_GCODE_VIEWER_DATA_CHECKING
 
     if (post_process)
-        m_time_processor.post_process(m_result.filename, m_result.moves, m_result.lines_ends);
+        m_time_processor.post_process(m_result.filename, m_result.moves, m_result.lines_ends, m_layer_id);
 #if ENABLE_GCODE_VIEWER_STATISTICS
     m_result.time = std::chrono::duration_cast<std::chrono::milliseconds>(std::chrono::high_resolution_clock::now() - m_start_time).count();
 #endif // ENABLE_GCODE_VIEWER_STATISTICS
diff --git a/src/libslic3r/GCode/GCodeProcessor.hpp b/src/libslic3r/GCode/GCodeProcessor.hpp
index e95527605..d29b18f32 100644
--- a/src/libslic3r/GCode/GCodeProcessor.hpp
+++ b/src/libslic3r/GCode/GCodeProcessor.hpp
@@ -224,7 +224,8 @@ namespace Slic3r {
             Custom_Code,
             First_Line_M73_Placeholder,
             Last_Line_M73_Placeholder,
-            Estimated_Printing_Time_Placeholder
+            Estimated_Printing_Time_Placeholder,
+            Total_Layer_Number_Placeholder
         };
 
         static const std::string& reserved_tag(ETags tag) { return Reserved_Tags[static_cast<unsigned char>(tag)]; }
@@ -422,7 +423,7 @@ namespace Slic3r {
 
             // post process the file with the given filename to add remaining time lines M73
             // and updates moves' gcode ids accordingly
-            void post_process(const std::string& filename, std::vector<GCodeProcessorResult::MoveVertex>& moves, std::vector<size_t>& lines_ends);
+            void post_process(const std::string& filename, std::vector<GCodeProcessorResult::MoveVertex>& moves, std::vector<size_t>& lines_ends, size_t total_layer_num);
         };
 
         struct UsedFilaments  // filaments per ColorChange