diff --git a/requirements.txt b/requirements.txt
index 94b5eb6..6f5ca58 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -6,6 +6,6 @@ MDAnalysis>=2.7.0
 PyWavelets>=0.5.2
 scikit-image>=0.14.2
 sphinx>=1.4.3 
-matplotlib
+matplotlib==3.9.3
 pytest
 dask>=1.1.1