diff --git a/activerecord/lib/active_record/connection_adapters/mysql2_adapter.rb b/activerecord/lib/active_record/connection_adapters/mysql2_adapter.rb
index c3c5b660fd..23b33a3555 100644
--- a/activerecord/lib/active_record/connection_adapters/mysql2_adapter.rb
+++ b/activerecord/lib/active_record/connection_adapters/mysql2_adapter.rb
@@ -42,7 +42,7 @@ module ActiveRecord
       end
 
       def supports_json?
-        version >= '5.7.8'
+        !mariadb? && version >= '5.7.8'
       end
 
       # HELPER METHODS ===========================================