diff --git a/src/calibre/gui2/tweak_book/spell.py b/src/calibre/gui2/tweak_book/spell.py
index 7bd3a45280..4cc6492dab 100644
--- a/src/calibre/gui2/tweak_book/spell.py
+++ b/src/calibre/gui2/tweak_book/spell.py
@@ -11,7 +11,7 @@ from collections import defaultdict, OrderedDict
 from threading import Thread
 from functools import partial
 
-from PyQt4.Qt import (
+from PyQt5.Qt import (
     QGridLayout, QApplication, QTreeWidget, QTreeWidgetItem, Qt, QFont, QSize,
     QStackedLayout, QLabel, QVBoxLayout, QWidget, QPushButton, QIcon, QMenu,
     QDialogButtonBox, QLineEdit, QDialog, QToolButton, QFormLayout, QHBoxLayout,