The invention discloses a ground stress extending, renovating and yield-increasing method for an oil-gas well. The ground stress extending, renovating and yield-increasing method comprises the following steps: S1, performing a field small crack diagnosis test, wherein geo-mechanical properties of an oil deposit are tested, and the geo-mechanical properties comprise three-dimensional main stress, permeability, reservoir pressure and crack fluid efficiency of a reservoir; S2, controlling injecting pressure to be greater than the smallest main stress of the reservoir and smaller than cracking pressure, adopting a circular hydraulic injection and reflow way at an inlet position, and improving ground stress and pore pressure around the well; S3, changing wellhead injection displacement, adopting an injection and reflow way, generating hydraulic shake in the reservoir to increase a pore volume, expanding micro crack and improving a seepage environment around the well; S4, performing low-sand-ratio injection, carrying silt in a low sand ratio, and supporting a hydraulic renovating region near the well; and S5, braising in the well for several days. The method is simple in process, is relatively low in construction cost, is relatively low in field equipment requirement, and is suitable for a compact sandstone reservoir, a shale reservoir and a reservoir with natural cracks.