The invention belongs to the technical field of uranium ore exploration, and particularly relates to a comprehensive geophysical and chemical exploration method for delineating a sandstone type uranium ore deep three-dimensional uranium mineralization target area. The method comprises the following steps: step 1, delineating an abnormal range of uranium content in fine-grained soil; step 2, carrying out aviation transient electromagnetic measurement, and delineating a favorable sand body range of uranium mineralization; 3, delineating a uranium mineralization key exploration area; 4, carryingout soil radon gas measurement, and delineating the abnormal range of the soil radon gas concentration; 5, carrying out controllable source audio magnetotelluric sounding, and delineating a deep uranium mineralization favorable sand body range; step 6, delineating a deep uranium mineralization favorable section; step 7, delineating a geoelectrochemical uranium content abnormal range; step 8, delineating a deep three-dimensional uranium mineralization favorable sand body range; and step 9, delineating a deep three-dimensional uranium mineralization target area. The method can solve the problemthat in the prior art, it is difficult to accurately delineate the sandstone type uranium ore deep three-dimensional uranium mineralization target area.