The invention provides a water-rich performance evaluation method based on sandstone microscopic characteristics. The method comprises the following steps that: firstly, determining a target water containing layer for water-rich performance evaluation, establishing the water-rich performance evaluation index system of the water containing layer, obtaining a lithology structure index, a flushing fluid consumption amount, porosity, permeability and pore diameter distribution, and drawing the thematic map of each evaluation index in S2 by GIS (Geographic Information System) software; according toexpert experience, drawing an expert marking table to calculate the contribution degree of each evaluation index for the water-rich performance, and obtaining the weight coefficient of each evaluation index; and overlapping each thematic map according to the weight coefficient of corresponding evaluation index, utilizing the GIS software to draw a water-rich performance evaluation map of sandstones, and carrying out sandstone water-rich performance evaluation. By use of the method, five indexes are adopted to increase water-rich performance evaluation accuracy, the water-rich performance of the water containing layer of the sandstone is researched from a micro perspective for the first time, and the continuous change and the structural variation of water containing media on an aspect of space are reflected.