Polishing is one of the important methods in manufacturing of Si wafers and in thinning of completed device wafer. This study will report the evaluation on abrasion of wafer according to processing time; machining speed and pressure which have major influence on the abrasion of Si wafer polishing, for this, this study design the head unit and analysis head unit. After that, apply to experiment. It is possible to evaluation of wafer abrasion by load cell and infrared temperature sensor. The evaluation of abrasion according to processing condition is selected to use result data that measure a pressure, machining speed, and the processing time. This result is appeared by abrasion in machining condition. Through that, the study cans evaluation a wafer abrasion in machining. It is important to obtain mirror-like wafer surface.