diff --git a/pelican/server.py b/pelican/server.py
index c4607e21..92b6ad76 100644
--- a/pelican/server.py
+++ b/pelican/server.py
@@ -120,6 +120,11 @@ class ComplexHTTPRequestHandler(server.SimpleHTTPRequestHandler):
         if mimetype == "application/octet-stream" and magic_from_file:
             mimetype = magic_from_file(path, mime=True)
 
+        # On some systems, JavaScript files are incorrectly assigned the "text/plain"
+        # MIME type in Python's mimetypes module. Override this behavior when it occurs.
+        if posixpath.splitext(path)[1] == ".js" and mimetype == "text/plain":
+            mimetype = "text/javascript"
+
         return mimetype
 
     def log_message(self, msg_format, *args):