A keypad assembly (20) is described that includes a housing (100) and a keypad (200) connecting with the housing. The housing has a keyhole area (144) formed thereon, and the housing has at least one keyhole (146) defined therein and a groove (148) is placed along a periphery of the keyhole area. The keypad has a key area (201) formed thereon, and the key area has at least one key (202) formed thereon and a projection (204) placed therearound to engage in the groove. A main advantage of the keypad assembly is that it can simplify the configuration of the seal while maintaining a good seal, and it also can reduce the production cost.