Abstract: Objective To investigate the effect of water insouble nickle(Ni)compounds on cellular Ni contents.Methods After 48 hours exposure of various concentrations of water insoluble NOi and Ni3S2,the cellular Ni concentration in human lung cancer A 549 cells was detected by a tomic absorption spectropho tometer(AAS)to estmiate the up take rate.Results After treated with concentrations of 0,0.5,1.0,1.5,2.0,2.5,3μg/cm² of Ni3S2,the Ni concentrations in every 10⁵ cells were 0.0024,0.0771,0.01574,0.2268,0.4754,0.7,and 0.9882μg,respectively.At the concentations of 0,0.5,1.0,2.0,4.0,8.0,and 16μg/cm² of NOi,the Ni concentrations in every 105 cells were 0.003,0.07,0.108,0.255,0.628,1.543,and 6.571μg,respectively.At the same concentraions(0.5,1.0,2.0μg/cm²),Ni concentrations of the cells treated with Ni3S2 were 0.0771±0.0066,0.1574±0.0190,and 0.4754±0.1121,and higher than that of NOi treated cells(00701±0.0032,0.1081±0.0159,0.2552±0.0415)with significant difference between the two groups(P<0.05).Conclusion The up take of water insouble Ni compound is dose dependent and the uptake rate of Ni3S2 is higher than that of NOi at the same Ni concentration.