Abstract: Nucleation,which has an extremely great impact on the quality of diamond films,is an import process of HFCVD diamond film depositing.Nucleation based on tiny hard alloy milling cutters was discussed in this article to achieve depositing high quality diamond films.Considering that there are lots of factors impacting the process of nucleation,we selected several nuclear factors,including filament power(P_f),the ratio of methane to hydrogen(X),and the pressure(p),and designed L9(33) orthogonal experiment,then investigated the impact of those factor on nucleation size,coverage,and nucleation quality via scanning electron microscope(SEM),Raman spectroscope,and EDS energy spectrum analysis.It turned out that filament power impacted nucleation size and nucleation rate greater,while pressure impacted that less,filament power and pressure impacted nucleation quality greater,while the ratio of methane to hydrogen impacted that less.We got the optimal nucleation parameters setting,P_f=2000W,X=2.0%,p=1 400 Pa.