diff --git a/pandas/formats/format.py b/pandas/formats/format.py
index 34e59b2977319..c16f1ce4f49ac 100644
--- a/pandas/formats/format.py
+++ b/pandas/formats/format.py
@@ -1826,7 +1826,7 @@ def __call__(self, declarations_str, inherited=None):
 
             if val is None:
                 # we do not define a complete initial stylesheet
-                del props[val]
+                del props[prop]
             else:
                 props[prop] = val
 
@@ -1984,7 +1984,8 @@ class CSSToExcelConverter(object):
 
     def __init__(self, inherited=None):
         if inherited is not None:
-            inherited = self.compute_css(inherited, sefl.INITIAL_STYLE)
+            inherited = self.compute_css(inherited,
+                                         self.compute_css.INITIAL_STYLE)
 
         self.inherited = inherited
 
diff --git a/pandas/tests/formats/test_to_excel.py b/pandas/tests/formats/test_to_excel.py
index de24e62f2d2a1..99a4ed6259ddd 100644
--- a/pandas/tests/formats/test_to_excel.py
+++ b/pandas/tests/formats/test_to_excel.py
@@ -176,3 +176,21 @@ def test_css_font_size_invalid():
 def test_css_to_excel(css, expected):
     convert = CSSToExcelConverter()
     assert expected == convert(css)
+
+
+@pytest.mark.parametrize('css,inherited,expected', [
+    ('font-weight: bold', '',
+     {'font': {'bold': True}}),
+    ('', 'font-weight: bold',
+     {'font': {'bold': True}}),
+    ('font-weight: bold', 'font-style: italic',
+     {'font': {'bold': True, 'italic': True}}),
+    ('font-style: normal', 'font-style: italic',
+     {'font': {'italic': False}}),
+    ('font-style: inherit', '', {}),
+    ('font-style: normal; font-style: inherit', 'font-style: italic',
+     {'font': {'italic': True}}),
+])
+def test_css_to_excel_inherited(css, inherited, expected):
+    convert = CSSToExcelConverter(inherited)
+    assert expected == convert(css)