In order to provide the test analysis technology to support the exploration　and development of niobium and tantalum resource,based on the special chemical properties of Nb and Ta in geochemical sample,we studied the detection methods for the content of Nb and Ta in geochemical sample by using inductively coupled plasma mass spectrometry (ICP-MS).The results show that the sample dissolution and instrumental parameter of ICP-MS,especially the former have significant　influence?on detection results.Therefore,optimizing important parameters of sample dissolution is the key of the detection technology.The optimal parameters are that:the weight of sample is 50　mg;the dosage of HF acid is 15　mL;the concentration of nitric acid and tartaric acid in the sample solution is 2% and 1.5%,respectively;the validity period of detection for sample solution ≤1　d.The detection method has been validated by the national geochemistry standard reference material.The precise and exaction of method meet the required of industry standards.The detection limits of method for Nb and Ta are 1.05 and 0.13　μg·g-1,respectively.The experiment proved that the ICP-MS detection methods,which using certain preparation process of sample solutions,is suitable for accurate and rapid　determination of Nb and Ta in geochemical sample,especially geochemical survey samples which with a large　amount and low　content　of　Nb and Ta.