The influences of Built-up Edge(BUE) phases of a rake face on the characteristics of surface profile of micro cutting were researched, which provided the proof for the optimal selection of cutting parameters and the evaluation for the characteristics of surface profile of micro cutting. The surface profile data in micro cutting were measured with a profilometer in different BUE phases, BUE free, BUE formation, BUE stable and BUE drop. The influences of the BUEs on the characteristics of machined surface profiles were analyzed with mathematical statistical functions such as Amplitude Density Function(ADF), Auto-correlation Function(ACF) and Power Spectral Density Function(PSD), as well as the time series model parameters and Auto Regression(AR) spectra. Obtained results indicate that in BUE free and BUE stable phases, the AR spectral peaks of micro cutting surface locate at 91.7 c/mm and 93.7 c/mm, respectively, which are very close to the reciprocal of a feed rate; while in BUE formation and BUE drop phases, the spatial frequency is significantly low compared with the reciprocal of feed rate. It is concluded that the consistency of the surface profile is deteriorated by the irregular contact between BUE and chip,and the low spatial frequency component becomes more dominant in the AR spectra of machined surface profile during BUE formation and BUE drop phases.