Silicon (Si) and its native oxide exhibit high friction and poor wear resistance especially at micro/nano-scale, thereby greatly limiting the applications of silicon-based dynamic micro-device. Here, a simple method through running-in at low sliding speed is proposed to achieve self-lubrication of oxidized Si (Si-SiOx) against SiO2 microspherical tip at nanoscale. In humid air, silicon material is extremely easy to suffer wear because of water-associated tribochemical-reaction. There exists a threshold sliding speed around 0.5 mu m/s below which the tribochemical wear of Si is suppressed and the friction force can be reduced significantly after initial running-in process. Analysis indicates that this self-lubrication state origins from modification of the SiO2 micro-tip surface. Low sliding speed with enough shear time may benefit to formation of a hydrophobic tip surface and generation of lubrication products in the tribochemical reaction, resulting in weak tribochemical wear and low friction force. Using this modified SiO2 tip, the excellent wear resistance and low friction property can be extended to the conditions of high sliding speeds ( > 0.5 mu m/s). These results will help for understanding the nanotribological behaviors of Si material and developing a simple method to control the nanotribological problems involved in the applications of silicon-based dynamic micro-device.