The present invention discloses a housing assembly of a portable electronic device. The housing assembly includes the first housing having a clasp and the second housing having a clasp and a clip. The first and second plates have latches and are slidably disposed on the first housing respectively. When the first and second housing are assembled together, the clasps on the first and second housings are joined together. Subsequently, the first and second plates slide and the clips are coupled to the latches. The first and second plates may be replaced by a U-shape plate. The U-shape plate is slidably disposed on the first housing and has a latch. When the first and second housing are assembled together, the clasps on the first and second housings are joined together. Subsequently, the U-shape plate slides and the clip is coupled to the latch.