Abstract: In determination of microamount of elements in basalts, the sample pretreatment step should be taken to remove the foreign inclusions, such as carbonate, from the pore of the basalts in order to get micro-mount of element distribution features in research area correctly. Therefore, ICP-MS with three different sample pretreatment methods was used to determination of microamount of elements in three Cenozoic basalt samples from Leizhou Peninsula, South China. The results indicated that pretreatment of the sample by dilute HNO3 could cause heavy lose for most micro-amount of elements in basalts and pretreatment of the sample by dilute HCl could gain the reliable results for micro-amount of elements. 