diff --git a/hgext/convert/common.py b/hgext/convert/common.py
--- a/hgext/convert/common.py
+++ b/hgext/convert/common.py
@@ -385,8 +385,12 @@ class mapfile(dict):
                 raise
             return
         for i, line in enumerate(fp):
+            line = line.splitlines()[0].rstrip()
+            if not line:
+                # Ignore blank lines
+                continue
             try:
-                key, value = line.splitlines()[0].rstrip().rsplit(' ', 1)
+                key, value = line.rsplit(' ', 1)
             except ValueError:
                 raise util.Abort(
                     _('syntax error in %s(%d): key/value pair expected')
@@ -418,8 +422,12 @@ def parsesplicemap(path):
     try:
         fp = open(path, 'r')
         for i, line in enumerate(fp):
+            line = line.splitlines()[0].rstrip()
+            if not line:
+                # Ignore blank lines
+                continue
             try:
-                child, parents = line.splitlines()[0].rstrip().split(' ', 1)
+                child, parents = line.split(' ', 1)
                 parents = parents.replace(',', ' ').split()
             except ValueError:
                 raise util.Abort(_('syntax error in %s(%d): child parent1'
diff --git a/tests/test-convert-splicemap.t b/tests/test-convert-splicemap.t
--- a/tests/test-convert-splicemap.t
+++ b/tests/test-convert-splicemap.t
@@ -67,10 +67,12 @@ splice repo2 on repo1
   $ cat > splicemap <<EOF
   > $CHILDID1 $PARENTID1
   > $CHILDID2 $PARENTID2,$CHILDID1
+  > 
   > EOF
   $ cat splicemap
   527cdedf31fbd5ea708aa14eeecf53d4676f38db 6d4c2037ddc2cb2627ac3a244ecce35283268f8e
   e4ea00df91897da3079a10fab658c1eddba6617b e55c719b85b60e5102fac26110ba626e7cb6b7dc,527cdedf31fbd5ea708aa14eeecf53d4676f38db
+  
   $ hg clone repo1 target1
   updating to branch default
   3 files updated, 0 files merged, 0 files removed, 0 files unresolved
diff --git a/tests/test-convert-svn-branches.t b/tests/test-convert-svn-branches.t
--- a/tests/test-convert-svn-branches.t
+++ b/tests/test-convert-svn-branches.t
@@ -14,6 +14,8 @@ Convert trunk and branches
 
   $ cat > branchmap <<EOF
   > old3 newbranch
+  >     
+  > 
   > EOF
   $ hg convert --branchmap=branchmap --datesort -r 10 svn-repo A-hg
   initializing destination A-hg repository