BERO™ biosurfactant is currently the world-leading product used for MEOR (microbial enhanced oil recovery) and it is a kind of non-active enzyme preparation using microorganism as matrix. It utilizes modern bioengineering technologies such as genetic engineering, cell engineering and enzyme engineering and can efficiently release hydrocarbon (oil) on the surfaces of solid particles. After being injected into a well, BERO™ biosurfactant can rapidly strip wax and asphalt crystallized and accumulated on rock particles in the area of a reservoir close to well and part of BERO™ biosurfactant adheres to rock surface to make the wettability of the rock become water-wetting, lower the flowing resistance of crude oil in formation voids, thus releasing crude oil from rock particle surface and being separated out from micropores. BERO molecules entering into water can be transported to the area further than the surrounding area of sandstone formation and form new oil outlet passages in sandstone formation so as to clean production well in oil reservoir, pl ing removal and injection reduction of water injection well, pl ing removal and stimulation, displacement and improving oil recovery rate.