Quantum radar can effectively overcome the effects of complex electromagnetic environment and target stealth characteristics based on the characteristics of quantum states to the detection and the recognition of targets. Aimed at the problem that the light quantum is susceptible to medium absorption and scattering while propagating in the atmosphere, a method of simulating atmospheric media using a spectroscopic link is proposed. The scattering cross section of the target quantum radar is studied. By introducing the single photon wave equation and using the optical splitting link to simulate the atmospheric medium, the photon wave function under the attenuation condition is obtained, and the quantum radar scattering cross section formula is deduced under the attenuation condition, and the singlecurved quantum radar cross section under the attenuation condition is simulated. The simulation results show that the peak value of the main lobe of the quantum radar scattering section decreases with the increase of the attenuation coefficient at different incident angles, and the incident angle has no effect on the quantum radar cross section; The peak of the petal for the target quantum radar cross section increases with the wavelength when the temperature is at 0 ℃ and the visibility is 30 meters.