Abstract: Beginning with the analysis of distribution and geo-chemical characteristics of Hydrogen (H₂) and Helium (He) in the crust, the paper demonstrates their sensitivities to earthquake occurrence and cites some typical earthquake exam ples home and abroad. At the same time, the paper points out that as abyssal gases, H₂ and he have interference anomalies in their behaviors. Am ong them those that caused by the exploration of underground thermal water are prominent. So it is necessary to do further work on the interference while conducting further development on precursor observation of H₂ and He.

Key words: Hydrogen, Helium, Pre-seismicanomaly, Interference