The invention discloses an antique brass imitating sign and a preparation method thereof. The antique brass imitating sign comprises a bottom plate, and the surface of the bottom plate is evenly coated with antique brass imitating paint in spray coating, rolling coating and/or brushing modes. The antique brass imitating paint is prepared from, by weight, 30-50 parts of potassium silicate, 10-20 parts of silica sol, 1-5 parts of 3-(trimethoxysilyl)propyl methacrylate, 0.1-1 part of sodium hexametaphosphate, 8-18 parts of pigment powder, 25-55 parts of water, 1-5 parts of inorganic antibacterial agent and 0.5-1.5 parts of antistatic agent. According to the antique brass imitating sign, through reasonable matching, the variety and use quantity of the inorganic antibacterial agents suitable for improving use performance of the antique brass imitating paint are preferentially selected, antibacterial performance is improved, antistatic performance is good, construction difficulty is reduced, and construction time is saved.