To achieve a reasonable selection of water lubricated stern tube bearing of ship stern shaft under different working conditions,common plastic and metal plastic synthetic rubber bearing under freshwater and seawater lubrication was tested on the friction wear test machine to compare their wear behaviors.Through accelerated test,the wear life two kinds of rubber bearings was compared.The results show that the friction coefficient and wear rate of two kinds of bearings are higher under seawater lubrication than under freshwater lubrication.Under seawater lubrication,the friction coefficient and wear rate of ordinary rubber bearings are smaller,and the normal service life is higher than those of synthetic rubber bearings,whereas in freshwater lubrication it is the opposite.Therefore,when lubricated by freshwater,it is suitable for adopting metal plastic synthetic rubber bearings,when lubricated by seawater,it is suitable for adopting ordinary rubber bearings.