Abstract: According to application requirement for remote telemetry and telecommand in aerospace engineering field, this paper has designed a three-wire synchronous serial data interface on AMBA 2.0 APB bus.In the constraints of gating and synchronous clock signals,the interface transfer serial data with peripheral equipment through independent data transceiver channels.At the rising edge of synchronous clock,the receiver collect data;at the falling edge of synchronous clock,the transmiter transmit data.Because of the FIFO integrated in the interface the design achieve the data buffer function.At present the interface has been applied in practical projects,and can largely meet the requirements for the functions and efficency in data communication.