An infrared wireless communication system is designed in 10Base-T Ethernet based on point-to-point infrared wireless communication. The wireless data communication in Ethernet is achieved through transforming Manchester code to 4PPM code and Ethernet data frames are re-packaged to be transmitted in physical layer by infrared wireless card. The transmission media of Ethernet is changed from unshielded twisted paired cable to infrared light. According to the character of infrared transceiver, optical collimation lens is applied in the infrared wireless communication system to extend the transmission distance of infrared transceiver.