The invention discloses an economical environment-friendly polymer cement waterproof paint. The paint is composed of a liquid component and a solid constituent in a mass ratio of 1:(1-3). The liquid component comprises the following substances in percentage by mass: 80-95% of styrene-acrylate copolymer emulsion, 0.1-0.3% of propanediol, 0.1-0.3% of defoaming agent, 1-2% of 2,5-di-tert-butyl hydroquinone and the balance of water. The solid constituent comprises the following substances in percentage by mass: 10-20% of ceramic brick polishing powder, 20-40% of quartz sand tailing powder, 0.5-5% of organic montmorillonite, 1-2% of polycarboxylate water reducing agent and 35-60% of P.O 42.5 ordinary Portland cement. The components of the polymer cement waterproof paint are scientifically matched; abundant polishing brick waste residues and quartz sand tailings are utilized in the paint, thereby obviously relieving the environmental protection pressure of the waste discharge enterprise, lowering the production cost, and changing wastes into valuable substances; and the waterproof coated film has the advantages of high bonding firmness with the substrate, favorable water resistance, favorable weather resistance and favorable cracking resistance.