This research subject came from National High-Tech Research and Development Programs (863) ----“Project of Chip Design and Application System Development of Ultra-low Power Wireless Portable Base Station SoC for Endoscopy Applications”. Multi-frequency multi-mode reconfigurable wireless portable base station SoC was developed. This SoC was composed of receiver RF front-en, transmitter RF front-end, receiver analog baseband processing module, transmitter analog baseband processing module, ADC/DAC, digital baseband processing unit containing MSK, ASK modulator/demodulator, LDO, etc. The SoC can be used in different applications. It supported three frequency bands (400-440MHz, 860-940MHz, 2400-2500MHz), two modulating modes (ASK and MSK), any data rate ranging from 1kbps to 3Mbps, and the outputting power of transmitter was controllable.