The invention discloses a stable photoelectric oscillator. The stable photoelectric oscillator comprises a 
laser device, an electro-
optical modulator, a long 
optical fiber, a photoelectric 
detector, an 
amplifier, an electric band-pass filter, an electrically-controlled 
microwave phase shifter, a high-stability 
microwave source, a 2*1 wave combiner or directional coupler, a first 1*2 power divider or directional coupler, a second 1*2 power divider or directional coupler, a third 1*2 power divider or directional coupler and a 
phase locking control module, wherein the 
phase locking control module comprises a 
frequency mixer, an electric 
low pass filter and a 
servo control module, the output end of the 
frequency mixer is connected to the input end of the electric 
low pass filter, and the output end of the electric 
low pass filter is connected to the input end of the 
servo control module. According to the stable photoelectric oscillator, an electric injection of the external high-stability 
microwave source and a 
phase locking control mechanism are added based on a traditional single-loop OEO structure. Compared with the prior art, the stable photoelectric oscillator has the advantages that 
insertion loss of an 
optical link in a 
resonant cavity is not increased, the high 
signal to 
noise ratio of the photoelectric 
resonant cavity is maintained, and the structural complexity of the stable photoelectric oscillator is lower than that of an existing scheme. The stable photoelectric oscillator is easy to obtain.