diff --git a/cinder/backup/chunkeddriver.py b/cinder/backup/chunkeddriver.py
index 490baf84458..8f003329bc8 100644
--- a/cinder/backup/chunkeddriver.py
+++ b/cinder/backup/chunkeddriver.py
@@ -78,7 +78,7 @@ def _write_nonzero(volume_file, volume_offset, content):
         # The len(chunk) may be smaller than chunk_length. It's okay.
         if not volume_utils.is_all_zero(chunk):
             volume_file.seek(volume_offset + chunk_offset)
-            volume_file.write(chunk)
+            volume_file.write(chunk.tobytes())
 
 
 def _write_volume(volume_is_new, volume_file, volume_offset, content):
diff --git a/releasenotes/notes/bug-2082587-fix-type-passed-during-backup-restoration.yaml b/releasenotes/notes/bug-2082587-fix-type-passed-during-backup-restoration.yaml
new file mode 100644
index 00000000000..20b6c40027d
--- /dev/null
+++ b/releasenotes/notes/bug-2082587-fix-type-passed-during-backup-restoration.yaml
@@ -0,0 +1,5 @@
+---
+fixes:
+  - |
+    `Bug #2082587 <https://bugs.launchpad.net/cinder/+bug/2082587>` _: Fixed
+     backup restoration throwing TypeError on new volume.