A bucket is a container that is used to store objects in Object Storage Service (OSS). Every object is contained in a bucket. You can configure a variety of bucket attributes such as the region, access control list (ACL), and storage class. You can create buckets of different storage classes to store data.

Naming conventions

The maximum number of buckets that can be created by using an Alibaba Cloud account within a region is 100. After a bucket is created, its name cannot be modified. OSS supports the following bucket naming conventions:

  • The name of a bucket must be unique in OSS in an Alibaba Cloud account.
  • The name can contain only lowercase letters, digits, and hyphens (-).
  • The name must start and end with a lowercase letter or a digit.
  • The name must be 3 to 63 characters in length.


The following examples of bucket names are valid:

  • examplebucket1
  • test-bucket-2021
  • aliyun-oss-bucket

The following examples show invalid bucket names and the reasons why the names are invalid:

  • Examplebucket1 (Uppercase letters are included.)
  • test_bucket_2021 (Underscores (_) are included.)
  • aliyun-oss-bucket- (The name ends with a hyphen (-).)