Abstract: Aiming at the problems of shift of lubricant films on head slider, and dynamic change visualization of lubricant films on head slider, this paper presents caculation model of lubricant thickness distribution on a head slider surface using phase shift method, which is base on improved vertical-objective-based ellipsometric microscope (VEM). Measurement of lubricant film thickness is achived with this method. Taking nonpolar perfluoropolyether (PFPE) lubricant Z03 as a sample, ellipsometric microscope is calibrated; while taking polar PFPE lubricant Zdol4000 as a sample, dewetting on head slider surface is observed. Experimental results show measuring accuracy and resolution are 0.37 nm and 0.36 μm respectively. This can be reference for other visualization of nm lubricant films.