Abstract: The paper deals with the tribological behavior of the Polyoxymethylene (POM) against stainless steel (0Cr17Ni12Mo2) in a simulated environment of deionized water with simulated water depth of 0 to 300 m to investigate single factorial effect of pressure changes of the environment from varying simulated depth of water on the tribological properties of POM. The test results were compared with ones of dry friction under atmospheric pressure. Scanning white-light interfeerometry profilometer and scanning electron microscopy were used to measure and analyze surface morphology of test samples before and after tribological testing. Results show that simulated water depth affected markedly the wear of POM and the friction coefficient of POM/0Cr17Ni12Mo2 pairs,but affected insignificantly on the surface roughness of worn samples as well as the dominant wear mechanism of POM/0Cr17Ni12Mo2 pairs. The wear of POM and the friction coefficient of POM/0Cr17Ni12Mo2 pairs reduced with increase of simulated water depth from 0 to 300 m.