This study explores effects of different ablation-cell gases on the signal sensitivity and stability of elements in solid microanalysis by Laser ablation inductively coupled plasma mass spectrometry technique,by using NIST SRM 612 as a reference sample,and chosing the low,moderate and high mass elements such as Li（7)，Cu（63)，Y（89)，Cs（140)，Ru（175)，Th（232)，U（238) as research subjects.The results showed that there were good sensitivity and signal stability when using argon as ablation-cell gas under 0.85 L/min of argon and 0.70 L/min of carrier gas.The relative standard deviations（RSDs) were under 4% and the oxide formations（UO/U) were 0.27%.When using helium as ablation-cell gas,good sensitivity and signal stability were obtained at 0.95 L/min of argon as make up gas and 0.95 L/min of helium as carrier gas.The RSDs were about 4% and the oxide formations（UO/U) were 0.32%.The signals increased three times and the background values were very low when using helium as ablation-cell gas in comparison with using argon, and the detection limits of method were markedly improved.Therefore,helium is recommended as ablation-cell gas of the laser ablation-ICP-MS.