A hyperspectral imaging method based on dual-channel shearing interferometry is proposed and its signal-to-noise ratio (SNR) is analyzed. The spectral restoration SNR of interferometry spectral imaging system is introduced. The principle of dual-rectangle shearing interferometry and SNR of dual-channel differential detection are discussed and simulated. The experimental apparatus is built, and the SNR contrast experiment of the actual scene target is carried out. The spectral detection SNR of dual-channel differential detection system is obtained, which is compared and analyzed with SNR of non-differential detection system. Results show that the spectral SNR of the proposed differential interferometry hyperspectral imaging system is 2 times as that of the single-channel system.