The invention discloses a method and a device for quantitatively distinguishing massive sandstones of the main body of a phase control sand body structure. The method comprises: dividing small layersand taking the comprehensive logging interpretation result as the object of the sand body structure research; performing linear correlation analysis on specified parameters and shale content, selecting top N items with better correlation as the basis of the comprehensive index method, and obtaining the threshold value of the specified parameters according to different log series values and core measured data corresponding to massive sandstones and bedding sandstones; determining a weight coefficient corresponding to each specified parameter; performing data standardization processing on top Nspecified parameters, and calculating the comprehensive index for the parameters after the data standardization processing, in which a weight based on the shale content is used as a coefficient and the directly/inversely proportional relationship of electrical characteristic of the massive sandstones is used as a basis; calculating the smoothness of the comprehensive index through a variance formula and a variation formula. According to the method and the device for quantitatively distinguishing the massive sandstones of the main body of the phase control sand body structure, the massive sandstones can be accurately identified to guide the fine exploration and development of lithological oil-gas reservoir.