diff --git a/markdownify/__init__.py b/markdownify/__init__.py
index 56854e8..33d5b8f 100644
--- a/markdownify/__init__.py
+++ b/markdownify/__init__.py
@@ -181,7 +181,11 @@ class MarkdownConverter(object):
     def convert_li(self, el, text):
         parent = el.parent
         if parent is not None and parent.name == 'ol':
-            bullet = '%s.' % (parent.index(el) + 1)
+            if parent.get("start"):
+                start = int(parent.get("start"))
+            else:
+                start = 1
+            bullet = '%s.' % (start + parent.index(el))
         else:
             depth = -1
             while el:
diff --git a/tests/test_conversions.py b/tests/test_conversions.py
index b8487e5..9e7be24 100644
--- a/tests/test_conversions.py
+++ b/tests/test_conversions.py
@@ -123,6 +123,7 @@ def test_i():
 
 def test_ol():
     assert md('<ol><li>a</li><li>b</li></ol>') == '\n1. a\n2. b\n\n'
+    assert md('<ol start="3"><li>a</li><li>b</li></ol>') == '\n3. a\n4. b\n\n'
 
 
 def test_p():