Self-assembly technique has been used to solve adhesion and friction problems in moving parts of micro-electro-mechanical systems (MEMS). In this paper, tetraethoxysilane/octadecyltrichlorosilane (TEOS/OTS) bilayer films were prepared by self-assembly on Si substrate. TEOS was firstly self-assembled on Si substrate as the interlayer and then OTS was grafted on the TEOS monolayers as the top layer. The morphology, chemical composition, wettability, and adhesion of the films were characterized. The prepared TEOS/OTS bilayer films were observed to be hydrophobic with uniform nanoclusters. The tribological properties of the films were performed on a ball-on-plate statnamic tribometer. Compared with Si substrate and OTS self-assembled monolayer (SAM), TEOS/OTS bilayer films exhibited reduced adhesion and improved tribological performance, which was attributed to the stable bilayer structure of TEOS as the interlayer and the transfer of the destroyed OTS SAM as the lubricating film. TEOS/OTS bilayer films are expected to improve the quality of the micro-parts in MEMS and reduce the abrasion of the micro-molds in microfabrication techniques.