A new algorithm is provided for carrier frequency offset acquisition for high dynamic signal with low SNR, and it is spectrum line shift algorithm. Firstly, current large carrier frequency offset acquisition technology is introduced, and the reason why this technology can’t adapt to high dynamic signal acquisition is analyzed. Secondly, carrier frequency offset acquisition affected by carrier frequency offset and its rate of change is analyzed. It’s mainly considered that Doppler frequency shift change rate affects signal’s acquisition. Doppler frequency shift change rate seriously reduces non-coherent accumulation number during carrier frequency offset estimation at low SNR. On this base, spectrum line shift algorithm is provided and researched, and it can adapt to large carrier frequency offset acquisition for high dynamic signal with low SNR. It’s shown that the algorithm has improvement of gain of 2-3dB, and compared with ML, the algorithm has absolute advantage by MATLAB simulation.