The invention discloses a II-type polymer cement waterproofing coating modified by nano materials, which consists of a liquid material component and a powder material component, wherein the liquid material component comprises the following ingredients by weight: 85-95 percent of acrylic ester latex, 0.5-2 percent of plasticizer, 0.2-0.4 percent of dispersant, 0.2-0.5 percent of silicone antifoam agent, 0.1-0.3 percent of preservative, 0.3-0.6 percent of active ingredient content of pre-dispersed nano silicon dioxide solution, 0.02-0.06 percent of active ingredient content of pre-dispersed nano alumina solution, and the balance of water. The mixture ratio of the liquid material component to the powder material component is 10:14-20 according to proportions by weight. The invention greatly improves the thixotropy of the coating, prevents coating elevation construction from sagging, reduces loss in coating construction, simultaneously enhances all properties of the coating such as water resistance, alkaline resistance and the like, and obtains obvious effects.