Abstract: There were three explosions on January 6, 2016, September 9, 2016, and September 3, 2017. Using the data of Hailar seismic array, the amplitudes of P-phase and Lg-phase of the three explosions were picked up, the amplitude spectrum were calculated, the magnitude were measured and the yield were estimated. The m_b （P） of short-period body wave magnitude calculated by using the national standard of magnitude are 5.3±0.1, 5.6±0.1 and 6.1±0.1, respectively. The m_b （Lg） of short-period body wave magnitude calculated by using the third peak method of Lg-phase are 4.33±0.05, 4.56±0.4和5.60±0.03, respectively. The low-frequency component of Lg-phase for the event of 2017 is more developed than that of the previous two events, and the amplitude is relatively larger, which is inferred to be related to the explosion damage mechanism or explosion technical process. The average yield results obtained by m_b （P） and m_b （Lg） through the magnitude-yield empirical formula were taken as the yield results of the three events, which were 14.4±4.3, 34±11.6 and 190.4±45.4 kt, respectively. The energy of the explosion event in 2017 was 5.6 times that of the event in September 2016 and 13.2 times that of the event in January 2016.