A woofer speaker is provided, comprising a woofer speaker unit, a first sealing pad, a second sealing pad and a housing. The first sealing pad is fixed closely with the outer edge of the housing; the woofer speaker unit is fixed and sealed within the housing by the first sealing pad, and the second sealing pad is located between the woofer speaker unit and the housing; a sound hole is provided on the housing, and the shape and size of the sound hole correspond to those of the woofer speaker; and the terminal installation plane is the rear cover of the woofer speaker, and together with the housing forms the rear sound cavity of the woofer speaker through the first sealing pad. The cavity of the woofer speaker provided by the invention and the installation terminal applying the woofer speaker resolve the rear cover vibration problem of ultra-thin woofer speakers.