diff --git a/.github/workflows/run_test.yml b/.github/workflows/run_test.yml
index b24c800..56cd4ba 100644
--- a/.github/workflows/run_test.yml
+++ b/.github/workflows/run_test.yml
@@ -27,9 +27,9 @@ jobs:
             brew install gnuplot
             brew install octave
           else
-            curl --retry 3 -kL http://cdimage.debian.org/mirror/gnu.org/gnu/octave/windows/octave-7.3.0-w64-64.7z --output octave_7.3.0.7z
-            7z x octave_7.3.0.7z -ooctave -y
-            echo "$PWD/octave/octave-7.3.0-w64-64/mingw64/bin" >> $GITHUB_PATH
+            curl --retry 3 -kL http://cdimage.debian.org/mirror/gnu.org/gnu/octave/windows/octave-6.4.0-w64-64.7z --output octave_6.4.0.7z
+            7z x octave_6.4.0.7z -ooctave -y
+            echo "$PWD/octave/octave-6.4.0-w64-64/mingw64/bin" >> $GITHUB_PATH
           fi
       - name: Install octave-image (Windows and MacOS)
         if: ${{ runner.os != 'Linux' }}