In this paper, we describe an experimental study undertaken to investigate the most influenced factors on the surface cleanability of hard disk drive arm and provide the optimal settings to maximize surface cleanability or minimize liquid particle counting (LPC). This will lead to reduction in the operation cost and improvement in hard disk drive arm quality. The experimental design for the study was based on Taguchi technique. A 2 level and 4 factors orthogonal array was used for screening main factors. The results show the main factors and optimal setting of water temperature at 35 oC, ultrasonic frequency at 80 kHz, ultrasonic power level at 90 per cent of 2500 watts and cleaning time at 480 sec.