The invention discloses a method and device for implementing broadcast, a method and device for implementing multicast in a software defined network, and a computer readable storage medium. The invention comprises the following steps: a virtual scalable local area network tunnel terminal receives the broadcast packet forwarding control information sent by a controller of the software defined network; and the virtual scalable local area network tunnel terminal performs broadcast forwarding on the broadcast packet according to the broadcast packet forwarding control information after receiving the broadcast packet. The solution provided by the application is also capable of implementing broadcast and multicast when the broadcast and multicast function has not be deployed in the underlying network since a controller is provided to perform broadcast and multicast forwarding control.