A cloud data center tenant-level outbound rate limiting method includes: starting a timer, receiving and generating statistics of outbound packets of tenants in a current period, obtaining local traffic rate information of the tenants based on all the outbound packets of the tenants in the current period, and generating local bandwidth demand frames of the tenants based on the local traffic rate information of the tenants; when a timing of the timer reaches the end of the current period, sending the local bandwidth demand frames of the tenants to a switch; receiving a global bandwidth demand frame sent by the switch, and computing bandwidth budgets of the tenants based on the local traffic rate information of the tenants and the global bandwidth demand frames of the tenants; modifying rate limiting parameters, and limiting the rate of the outbound packets of the tenants in a next period.