A substrate processing apparatus which processes includes a thermal processor that performs thermal processing on the substrate; an imager that images the substrate; and a controller that executes adjustment processing of adjusting conditions of processing on the substrate. The adjustment processing includes: controlling the imager to image an unexposed adjustment substrate on which a resist film is formed; controlling the thermal processor to perform the thermal processing on the adjustment substrate subjected to uniform exposure processing of exposing each region of a substrate surface with a fixed exposure amount after the pre-exposure imaging; controlling the imager to image the adjustment substrate after the thermal processing; estimating an in-plane temperature distribution of the adjustment substrate in the thermal processing based on the pre-exposure imaging result and the post-heating imaging result; and deciding processing conditions of the thermal processing based on an estimation result of the in-plane temperature distribution.