The invention relates to a preparation method of an odorless environment-friendly humidifying antibacterial paint. The odorless environment-friendly humidifying antibacterial paint basically comprises 12-40% of emulsion, 5-20% of titanium white, 12-20% of kieselguhr, 2-6% of attapulgite, 4-8% of bamboo charcoal powder, 3-10% of nano TiO2/anion powder additive, 5-10% of light calcium carbonate, 5-10% of kaolin, 1-5% of propanediol, 2-5% of assistant and 10-30% of deionized water. The multifunctional humidifying antimicrobial internal wall paint completely satisfies various indexes specified in GB/T9756-2001, has the effects of temperature control, energy saving, environmental protection, moisture absorption and release, humidification, dewing resistance, air refreshing, no odor, deodorization, bacteria and mold inactivation and the like, and is widely used in inner wall application of habitable rooms, classrooms, offices, hospitals and the like.