diff --git a/swh/objstorage/backends/libcloud.py b/swh/objstorage/backends/libcloud.py
--- a/swh/objstorage/backends/libcloud.py
+++ b/swh/objstorage/backends/libcloud.py
@@ -47,12 +47,15 @@
 
     Args:
       container_name: Name of the base container
+      path_prefix: prefix to prepend to object paths in the container,
+                   separated with a slash
       compression: compression algorithm to use for objects
       kwargs: extra arguments are passed through to the LibCloud driver
     """
     def __init__(self,
                  container_name: str,
                  compression: Optional[str] = None,
+                 path_prefix: Optional[str] = None,
                  **kwargs):
         super().__init__(**kwargs)
         self.driver = self._get_driver(**kwargs)
@@ -60,6 +63,9 @@
         self.container = self.driver.get_container(
             container_name=container_name)
         self.compression = compression
+        self.path_prefix = None
+        if path_prefix:
+            self.path_prefix = path_prefix.rstrip('/') + '/'
 
     def _get_driver(self, **kwargs):
         """Initialize a driver to communicate with the cloud
@@ -119,8 +125,16 @@
 
         You almost certainly don't want to use this method in production.
         """
-        yield from (hashutil.bytehex_to_hash(obj.name.encode()) for obj in
-                    self.driver.iterate_container_objects(self.container))
+        for obj in self.driver.iterate_container_objects(self.container):
+            name = obj.name
+
+            if self.path_prefix and not name.startswith(self.path_prefix):
+                continue
+
+            if self.path_prefix:
+                name = name[len(self.path_prefix):]
+
+            yield hashutil.hash_to_bytes(name)
 
     def __len__(self):
         """Compute the number of objects in the current object storage.
@@ -174,7 +188,10 @@
     def _object_path(self, obj_id):
         """Get the full path to an object"""
         hex_obj_id = hashutil.hash_to_hex(obj_id)
-        return hex_obj_id
+        if self.path_prefix:
+            return self.path_prefix + hex_obj_id
+        else:
+            return hex_obj_id
 
     def _get_object(self, obj_id):
         """Get a Libcloud wrapper for an object pointer.
diff --git a/swh/objstorage/tests/test_objstorage_cloud.py b/swh/objstorage/tests/test_objstorage_cloud.py
--- a/swh/objstorage/tests/test_objstorage_cloud.py
+++ b/swh/objstorage/tests/test_objstorage_cloud.py
@@ -3,6 +3,7 @@
 # License: GNU General Public License version 3, or any later version
 # See top-level LICENSE file for more information
 
+from typing import Optional
 import unittest
 
 from libcloud.common.types import InvalidCredsError
@@ -93,6 +94,7 @@
 
 class TestCloudObjStorage(ObjStorageTestFixture, unittest.TestCase):
     compression = 'none'
+    path_prefix: Optional[str] = None
 
     def setUp(self):
         super().setUp()
@@ -100,6 +102,7 @@
             CONTAINER_NAME,
             api_key=API_KEY, api_secret_key=API_SECRET_KEY,
             compression=self.compression,
+            path_prefix=self.path_prefix,
         )
 
     def test_compression(self):
@@ -143,3 +146,17 @@
 
 class TestCloudObjStorageZlib(TestCloudObjStorage):
     compression = 'zlib'
+
+
+class TestCloudObjStoragePrefix(TestCloudObjStorage):
+    path_prefix = 'contents'
+
+    def test_path_prefix(self):
+        content, obj_id = self.hash_content(b'test content')
+        self.storage.add(content, obj_id=obj_id)
+
+        container = self.storage.driver.containers[CONTAINER_NAME]
+        object_path = self.storage._object_path(obj_id)
+
+        assert object_path.startswith(self.path_prefix + '/')
+        assert object_path in container