The invention provides a method for detecting a cement-based material sulfate erosion mechanism through solid nuclear magnetic resonance. The method comprises the steps: test pieces are cut in the thickness direction, one of the test pieces is selected at random to be sampled and then ground into powder, and 29 Si, 27 Al and 33 S nuclear magnetic analysis is conducted; additionally, m of the testpieces are taken to be subjected to nuclear magnetic analysis; nuclear magnetic information that the material corrosion age is zero day is comprehensively obtained; the remaining test pieces are fullywrapped, and after air drying, the top faces are cut away to enable the test pieces to be exposed in a single-face mode; the remaining test pieces are put into a sulfate dry and wet cycle simulationexperiment box, and a dry and wet cycle is set; after the preset number of times is reached, the test pieces are taken out, sampling is conducted according to the previous steps, and nuclear magnetic analysis is conducted; every time the specified number of cycle times is reached, the remaining test pieces are sampled to be subjected to nuclear magnetic analysis, and nuclear magnetic information that the test piece corrosion age is N days is obtained; and based on the nuclear magnetic information, the material compaction degree, change of products in the erosion process and the generating rate of the sulfate-containing products along with the erosion age are obtained, and thus the erosion mechanism and the damage accumulation situation are obtained.