diff --git a/translate/convert/test_po2yaml.py b/translate/convert/test_po2yaml.py
index cec9cafe2b..0647555ec9 100644
--- a/translate/convert/test_po2yaml.py
+++ b/translate/convert/test_po2yaml.py
@@ -130,6 +130,10 @@ def test_nested(self):
 msgid "booo"
 msgstr ""
 
+#: foo->
+msgid "bar2"
+msgstr ""
+
 #: eggs
 msgid "spam"
 msgstr ""
@@ -137,21 +141,25 @@ def test_nested(self):
         template_string = '''
 foo:
     bar: bar
+    '': bar2
     baz:
         boo: booo
 eggs: spam
 '''
         target_store = self._convert_to_store(input_string, template_string)
-        assert len(target_store.units) == 3
+        assert len(target_store.units) == 4
         assert target_store.units[0].getlocations() == ['foo->bar']
         assert target_store.units[0].source == "bar"
         assert target_store.units[0].target == "bar"
-        assert target_store.units[1].getlocations() == ['foo->baz->boo']
-        assert target_store.units[1].source == "booo"
-        assert target_store.units[1].target == "booo"
-        assert target_store.units[2].getlocations() == ['eggs']
-        assert target_store.units[2].source == "spam"
-        assert target_store.units[2].target == "spam"
+        assert target_store.units[1].getlocations() == ['foo->']
+        assert target_store.units[1].source == "bar2"
+        assert target_store.units[1].target == "bar2"
+        assert target_store.units[2].getlocations() == ['foo->baz->boo']
+        assert target_store.units[2].source == "booo"
+        assert target_store.units[2].target == "booo"
+        assert target_store.units[3].getlocations() == ['eggs']
+        assert target_store.units[3].source == "spam"
+        assert target_store.units[3].target == "spam"
 
     def test_convert_completion_below_threshold(self):
         """Check no conversion if input completion is below threshold."""
diff --git a/translate/convert/test_yaml2po.py b/translate/convert/test_yaml2po.py
index 98ff016e5b..ac8e911023 100644
--- a/translate/convert/test_yaml2po.py
+++ b/translate/convert/test_yaml2po.py
@@ -71,6 +71,7 @@ def test_nested(self):
         input_string = '''
 foo:
     bar: bar
+    '': bar2
     baz:
         boo: booo
 
@@ -78,16 +79,19 @@ def test_nested(self):
 eggs: spam
 '''
         target_store = self._convert_to_store(input_string)
-        assert self._count_elements(target_store) == 3
+        assert self._count_elements(target_store) == 4
         assert target_store.units[1].getlocations() == ['foo->bar']
         assert target_store.units[1].source == "bar"
         assert target_store.units[1].target == ""
-        assert target_store.units[2].getlocations() == ['foo->baz->boo']
-        assert target_store.units[2].source == "booo"
+        assert target_store.units[2].getlocations() == ['foo->']
+        assert target_store.units[2].source == "bar2"
         assert target_store.units[2].target == ""
-        assert target_store.units[3].getlocations() == ['eggs']
-        assert target_store.units[3].source == "spam"
+        assert target_store.units[3].getlocations() == ['foo->baz->boo']
+        assert target_store.units[3].source == "booo"
         assert target_store.units[3].target == ""
+        assert target_store.units[4].getlocations() == ['eggs']
+        assert target_store.units[4].source == "spam"
+        assert target_store.units[4].target == ""
 
     def test_no_duplicates(self):
         """Check converting drops duplicates."""
diff --git a/translate/storage/test_yaml.py b/translate/storage/test_yaml.py
index 701ba3a28e..e7c1dee7e9 100644
--- a/translate/storage/test_yaml.py
+++ b/translate/storage/test_yaml.py
@@ -350,6 +350,27 @@ def test_key_nesting(self):
   value: teststring2
 '''
 
+    def test_empty_key(self):
+        store = self.StoreClass()
+        store.parse('''
+'': Jedna
+foo:
+  '': Dve
+''')
+        assert len(store.units) == 2
+        assert store.units[0].getid() == ''
+        assert store.units[0].source == 'Jedna'
+        assert store.units[1].getid() == 'foo->'
+        assert store.units[1].source == 'Dve'
+        out = BytesIO()
+        store.serialize(out)
+        assert out.getvalue() == b'''? ''
+: Jedna
+foo:
+  ? ''
+  : Dve
+'''
+
 
 class TestRubyYAMLResourceStore(test_monolingual.TestMonolingualStore):
     StoreClass = yaml.RubyYAMLFile
diff --git a/translate/storage/yaml.py b/translate/storage/yaml.py
index 8514f2241e..05c60fac82 100644
--- a/translate/storage/yaml.py
+++ b/translate/storage/yaml.py
@@ -149,7 +149,7 @@ def get_root_node(self, node):
     def serialize(self, out):
         def nested_set(target, path, value):
             if len(path) > 1:
-                if len(path) == 2 and path[1][0] == '[' and path[1][-1] == ']' and path[1][1:-1].isdigit():
+                if len(path) == 2 and path[1] and path[1][0] == '[' and path[1][-1] == ']' and path[1][1:-1].isdigit():
                     if path[0] not in target:
                         target[path[0]] = []
                     target[path[0]].append(value)