The growth of molds on the surfaces of polychrome cultural relics will cause serious damage to cultural relics by changing the color and appearance and destroying the overall stability. An important method to prevent and control the mold damage is to use fungicides. Previous studies have found that different strains have different sensitivities to specific fungicides, and the concentration is not always the same. Therefore, in the face of complex and diverse molds in the actual conservation work for cultural relics, how does one select effective fungicides and adopt appropriate concentrations for mildew-proof treatments？ This has become the bottleneck problem of using fungicides to prevent polychrome cultural relics from being mildewed.In order to explore the methods for selecting the types and concentrations of fungicides for polychrome cultural relics, 12 kinds of fungicides, including isothiazolinone, tebuconazole, natamycin, clotrimazole, benzalkonium chloride, dichlorophenol, cinnamon essential oil, clove essential oil, thyme essential oil, basil essential oil, benzimidazole and nanosilver were selected, and five common molds found in polychrome cultural relics, including Penicillium chrysogenum, Aspergillus versicolor, Cladosporium sp., Alternaria alternata,and Aspergillus japonicus were used as the fungi being studied. The performances of these fungicides were systematically evaluated from the aspects of their antifungal activity, drug sensitivity, color change, antifungal effect and long-term effectiveness. In addition, a preliminary fungal control evaluation method system for the prevention and control of typical molds in polychrome cultural relics was developed:1) measuring the minimum inhibitory concentration (MIC) and the minimum bactericidal concentration (MBC) of the fungicides using 96-well plates for preliminary screening and also to determine whether the mold was resistant to the fungicide (according to MBC≥32MIC); 2) judging whether the fungicides will change the colors of polychrome cultural relics based on color difference values (ΔE); 3) using the spore germination rate to calculate the semi-maximum effective concentration of the fungicide (EC₅₀) and measuring the size of inhibition zone to evaluate the anti-mildew effect of the fungicides; 4) calculating the concentration of culturable fungi through the polychromy simulation experiments that monitor the long-term antifungal effect. The experimental results showed that, according to the constructed evaluation system, the fungicides (and their concentrations) with good antifungal effects and long-term effectiveness against the above five common molds were screened:0.15% isothiazolinone and tebuconazole, 2% benzalkonium chloride, cinnamon essential oil and clotrimazole. Moreover, benzalkonium chloride had strong long-term antifungal effects on the five molds. However, 0.2% natamycin caused color changes in some pigments. The fungicides were selected according to a number of indicators, and an innovative program and method system for evaluating the performance of fungicides with multiple parameters was constructed for the first time. These could fill the lack of current method systems for scientific evaluation of fungicides for polychrome cultural relics. This work provides a theoretical basis for the prevention and control of molds in polychrome cultural relics, and can have important guiding significance for the conservation of cultural heritage.