The invention relates to high-adhesion internal wall latex paint and a preparation method thereof. The high-adhesion internal wall latex paint is prepared from titanium dioxide, high titanium powder, salt gypsum powder, talcum powder, heavy calcium powder, photocatalysts, ethylene glycol monoethyl ether acetate, a defoaming agent, a dispersing agent, a thickening agent, an antioxidant, an mould inhibitor, deionized water, acrylic ester emulsion and herba bidentis tripartitae extracts. During the latex paint preparation, ordinary raw materials are added, and the herba bidentis tripartitae extracts prepared in a special mode are also added; after the partial contained ingredients are added into the latex paint, the scrubbing-resistant performance of the latex paint can be improved; in addition, the color of the latex paint is softer, brighter and whiter; the texture is finer and smoother.