Disclosed is a wireless speaker having a structure with the outer cover. The outer cover can be easily detached from the speaker body, facilitating user's mounting external electronic products as desired, for example, various types of bulbs, such as an LED or energy-saving lamp, and a wireless router or a camera. Also disclosed is a wireless speaker system, where the wireless set and the wireless speaker use wireless transmitting and receiving modules, or may use WiFi, Bluetooth or other wireless transmission modes. The wireless set supports a plurality of wireless speakers, and the wireless receiving speaker may be mounted on the ceiling, wall, or hidden place in a kitchen, living room, bedroom, bathroom or even bar, and restaurant; or even mounted on a table or floor lamp, or transportation means such as trains and planes, serving as a video and audio center for households and entertainment places by free combinations.