In this study, Ultra-precision finishing system using micro abrasive film experimented using experimental variable film feed speed and grinding speed and structural steel(SM45C) with respect to 12~3{mu}m$ micro abrasive film. the result are follows; (1) Experimental condition must setup dissimilar about each micro abrasive film. (2) To measurement deviation the smallest machined condition are 20mm/min in 12{mu}m$, 5mm/min and 15mm/min in 9{mu}m$ and 5{mu}m$, 5mm/min in 3{mu}m$ in film feed speed. (3) To measurement deviation the smallest machined condition are 180m/min in 12{mu}m$, 84m/min in 9{mu}m$, 56 and 84m/min in 5{mu}m$, 104m/min in 3{mu}m$ in grinding speed.