In order to analyze the measurement-device-independent quantum key distribution protocol more comprehensively, the statistical fluctuation analysis of measurement-device-independent quantum key distribution protocols based on heralded pair coherent state is carried out. First, with the increase of the number of transmitted signal pulses in the statistical fluctuation of light source, the relationships of bit error rate and key generation rate with transmission distance are analyzed. The results show that increasing the number of pulses can improve the key generation rate and the maximum transmission distance, and can reduce the bit error rate. Moreover, the measurement-device-independent quantum key distribution protocol based on heralded pair coherent state has better performance than the one based on heralded single photon sources. When the light source is statistical fluctuating, the relationship between the key generation rate and the transmission distance of measurement-device-independent quantum key distribution protocol based on heralded pair coherent state in asymmetric channels is further analyzed, and the simulation results show that this protocol in asymmetric channels has better performance than that in symmetric channels.