Abstract: Diamond thin film have been deposited in different nucleation temperature and growth temperature onto silicon(100)substrates using a gas mixture of methane and hydrogen by a microwave plasma chemical vapor deposition(MPCVD)from.The quality of diamond film was characterized by Raman spectrum respectively,X-ray diffraction(XRD)patterns and scanning electron microscopy(SEM).The experimental results show that the different nucleation temperature and growth temperature are important for the quality of diamond.When the nucleation temperature decreases,the content of non-diamond and secondary nucleation increases.As the growth temperature increases,the content of non-diamond phase is less,the quality of the diamond was improved,but a large number of diamond crystal faces was etched at the same time.