In order to solve the problem that air conditioning remote controllers are not compatible, in this paper, an intelligent air conditioning remote controller is designed based on Atmega 16. In the remote controller,the method of measuring pulse width is employed to learn infrared signals, and the RLE compression algorithm is applied for data storage. Infrared carrier is generated through PWM mode based on the internal timer of SCM. The remote controller successfully achieves the learning and reproduction functions,which could be controlled via PC. The running test results show that the system is flexible and stable. It provides a new scheme for designing an intelligent remote controller.