diff --git a/CHANGES b/CHANGES
index 618114357..8a8271901 100644
--- a/CHANGES
+++ b/CHANGES
@@ -12,6 +12,7 @@ Bugs fixed
 * #2640: 1.4.2 LaTeX crashes if code-block inside warning directive
 * Let LaTeX use straight quotes also in inline code (ref #2627)
 * #2351: latex crashes if enumerated lists are placed on footnotes
+* #2646: latex crashes if math contains twice empty lines
 
 
 Release 1.4.3 (released Jun 5, 2016)
diff --git a/sphinx/ext/mathbase.py b/sphinx/ext/mathbase.py
index 13a560c0a..ddcec492c 100644
--- a/sphinx/ext/mathbase.py
+++ b/sphinx/ext/mathbase.py
@@ -58,7 +58,7 @@ def wrap_displaymath(math, label, numbering):
             begin = r'\begin{align*}%s\!\begin{aligned}' % labeldef
             end = r'\end{aligned}\end{align*}'
         for part in parts:
-            equations.append('%s\\\\\n' % part)
+            equations.append('%s\\\\\n' % part.strip())
 
     return '%s\n%s%s' % (begin, ''.join(equations), end)