Aiming at acquiring accurately the CDMA2000 1x EVDO(Evolution-Data Optimized) uplink spread code under weak signal conditions, a joint acquisition algorithm based on short time correlation Fast Fourier Transform(FFT) and differential coherent accumulation is proposed. Firstly, the short time correlation and FFT algorithm is adopted to estimate the Doppler frequency offset accurately; the correlation peak is obtained by differential coherent accumulation of demodulated signal based on the frequency offset estimated value. Then by setting the adaptive decision threshold and accumulation length, the higher probabilities of detection are obtained; the acquisition sensitivity and computation complexity of the proposed algorithm are compared with that of the coherent accumulation algorithm. Finally, based on the measured data, simulation is performed and the results show that the acquisition sensitivity of the proposed algorithm is improved by about 1.5 dB than that of the coherent accumulation algorithm,and the computation complexity is lowered.