The ground microseismic weak signal curvelet coefficient has a small amplitude after curvelet transform;this part of the weak signal will be covered by the noise of curvelet coefficient.The conventional threshold function fails to differentiate effective weak signal from ineffective ones,and hence the effective weak signal will be removed as noise.For the ground weak signal in microseismic data processing,the weak signal should be tackled with less damage in noise suppression.In this paper,the authors put forward a compensation threshold algorithm on the basis of the conventional threshold function.The authors add a new threshold between the weak signal and noise,so that it can compensate the damaged weak signal overlapped with the noise of curvelet coefficient.Model test and actual data processing show that compensation threshold function algorithm is better in suppressing random and coherent noise of the microseismic data than the conventional threshold function.It can also improve the signal-to-noise ratio of data and achieve the purpose of weak signal detection.