Abstract: This paper discuses the relations between earth stress and oil reservoir remaking project in terms of theory, puts forward the technical principles and methods of using earth stress to direct the remaking of oil reservolr, points out:the shape of hydraulic fracture depends on the scale and direction of earth stress;with the increase of the minimum horizontal main stress, the operating pump pressure will increase, the demands on the strength of propping agent and the flow conductivity will be more high;the scale of earth stress affects the selection to fracturing fluid;the operating pump discharge capacity should be in direct proportion to the minlmum main stress. This paper also analyzes in detail the effects of the stress differential of the barriers and perforation intervals on the fracture height, stimulation effect and operating scale.