With the future wireless communication demand growth, communication systems need to apply more frequency bands and standards. Aiming at the shortcomings of the narrow operating bandwidth of reconfigurable power amplifiers in each mode, this paper proposes a design method to expand the operating bandwidth of reconfigurable power amplifiers based on the simplified real-frequency technique and reconfigurable theory. By incorporating the broadband design method of simplified real-frequency method in the reconfigurable theory, a new error function is added in the design process to discriminate the reconfigurable circuit structure in variable modes, then realize the reconfigurable broadband power amplifier design. In order to verify the effectiveness of the method and meet the actual design specifications, a frequency-switchable wideband reconfigurable power amplifier for GSM network and LTE network is designed and fabricated by using LDMOS transistors independently developed by the Institute of Microelectronics, Chinese Academy of Sciences. The test results show that the reconfigurable power amplifier can operate in the frequency bands of 0. 6 ~ 1. 1 GHz and 1. 1 ~ 1. 6 GHz in different modes, respectively, with a saturated output power of more than 40 dBm, and a drain efficiency (DE) of between 50% and 60%. Therefore, the design method proposed in this paper can reduce the design difficulty of reconfigurable broadband power amplifiers, better utilize the transistor performance, and reduce the cost, which is of great significance for application in the design of RF circuits of practical base stations.