diff --git a/swh/model/hypothesis_strategies.py b/swh/model/hypothesis_strategies.py
--- a/swh/model/hypothesis_strategies.py
+++ b/swh/model/hypothesis_strategies.py
@@ -188,15 +188,16 @@
     ))
 
     if not only_objects:
-        # Make sure aliases point to actual branches
+        # Make sure aliases point to actual branches and no cycles exist
         unresolved_aliases = {
-            target.target
-            for target in branches.values()
-            if (target
-                and target.target_type == 'alias'
-                and target.target not in branches)
-         }
-
+            branch.target
+            for name, branch in branches.items()
+            if (branch
+                and branch.target_type == 'alias'
+                and (branch.target not in branches or
+                     (branches[branch.target] and
+                      branches[branch.target].target == name)))
+        }
         for alias in unresolved_aliases:
             branches[alias] = draw(branch_targets(only_objects=True))
 
diff --git a/swh/model/tests/test_hypothesis_strategies.py b/swh/model/tests/test_hypothesis_strategies.py
--- a/swh/model/tests/test_hypothesis_strategies.py
+++ b/swh/model/tests/test_hypothesis_strategies.py
@@ -9,7 +9,7 @@
 from hypothesis import given
 
 from swh.model.hashutil import DEFAULT_ALGORITHMS
-from swh.model.hypothesis_strategies import objects, object_dicts
+from swh.model.hypothesis_strategies import objects, object_dicts, snapshots
 
 
 target_types = (
@@ -60,3 +60,12 @@
     elif obj_type == 'snapshot':
         for branch in object_['branches'].values():
             assert branch is None or branch['target_type'] in target_types
+
+
+@given(snapshots(min_size=4))
+def test_generated_snapshot_branch_alias(snapshot):
+    for name, branch in snapshot.branches.items():
+        if branch and branch.target_type == 'alias':
+            assert branch.target in snapshot.branches
+            alias_target = snapshot.branches[branch.target]
+            assert not alias_target or alias_target.target != name