Food safety is directly affected by friction and wear in processing by food machinery.Soybeans and 316L stainless steel were chosen as friction pairs,and sliding friction and wear testing machine was used to study the influence of dry friction and water lubrication conditions on their tribological properties.The surface topography,roughness and worn surface composition of the specimen were analyzed respectively by optical microscopy,optical three-dimensional topography and infrared spectroscopy.The results show that the average friction coefficient of friction pair of soybean and 316L stainless steel is about 0.24 with much lower fluctuation under dry condition.The average friction coefficient under water lubrication condition is about 4.4 times of that under dry friction condition，with much more and bigger fluctuations in the friction process.Compared with dry friction,the wear mark width of stainless steel specimen and soybean specimen increases respectively by about 10% and as high as 1.6 times under water lubrication.More organic matter decomposed by soybeans is found on the worn surface of the stainless steel under water lubrication friction.The number and depth of the plough grooves on the worn surface of the stainless steels significantly reduced，and there are no plough grooves on the worn surface of the soybean specimen under water lubrication.The wear mechanism of soybeans and stainless steel under dry friction is mainly abrasive wear,while the adhesive wear increases significantly under water lubrication.