The invention relates to a key module used for being mounted in electronic equipment to realize automatic return functions, which comprises a casing, a key in pin joint with the inside of the casing and a spring plate fixed on the casing. The key is capable of pivoting in the casing against the spring plate which then deforms to push the key to return. The key module utilizes the spring plate to drive the key to return, and the spring plate with relatively thin thickness can obtain larger elastic force, thereby preventing the key being unable to return while unable to overcome the frictional force. In addition, the spring plate is quite thin and only occupies a little part of the thickness of the electronic equipment, thereby providing sufficient containing space for other electronic components in the electronic equipment. Therefore, the spring plate can be larger in size, which is convenient for being mounted in the electronic equipment.