diff --git a/.ci_support/environment.yml b/.ci_support/environment.yml
index b32704ff..3793a81b 100644
--- a/.ci_support/environment.yml
+++ b/.ci_support/environment.yml
@@ -4,7 +4,7 @@ dependencies:
 - ase =3.23.0
 - coverage
 - lxml =5.3.0
-- mendeleev =0.19.0
+- mendeleev =0.20.1
 - numpy =1.26.4
 - pandas =2.2.3
 - phonopy =2.33.4