The invention discloses a system and a method for improving radio frequency through broadband wireless communication, and belongs to the technical field of wireless communication, and the system comprises a photoelectric modulator, a photoelectric converter, and a laser. According to the invention, the requirements of radio frequency on a high-speed ADC and a microwave circuit are greatly reduced,and a traditional PLL reference clock configurator is used as a clock source for simulating up-conversion. The clock frequency is influenced by devices, circuits and the like, the design is complex when the frequency is about 100GHz, the cost is relatively high, according to the invention, a broadband photoelectric modulation principle is utilized, under the condition that data transmission is not affected, signals are modulated through laser and then converted into electric signals through a photoelectric converter, due to the fact that the adjustable range of the wavelength of light waves is large, the radio frequency can be greatly improved, a PLL reference clock configurator and a high-speed DAC are omitted, and finally the purposes of improving performance and reducing device complexity are achieved.