Nano-sized patterns resulted from localized electrochemical oxidation by using atomic force microscopy (AFM) were fabricated on H-passivated Si surface. In this paper, the fabrication of nanopattern by local anodic oxidation (LAO) on H-passivated Si surface is presented. A special attention is paid to finding relations between the size of oxide nanopatterns and operational parameters such as tip-sample pulsed bias voltage, pulsewidth and relative humidity to fabricate oxide nanopattern. The LAO process shows the highly potential of solution processes for fabricating nano/micro-devices constructed from semiconductor materials for visible-light-emitting devices.