Objective To determine the inhibitory effect of skin resident bacteria under the action of different preservatives. Methods Combined with the collected real-time data, the minimum inhibitory concentration value (MIC) was calculated first, the initial constraint conditions were set, and then the bacteria were cultured. The change state of the number of colonies was compared in multiple cycles, and the average value of colony change was calculated to determine and analyze the treatment effect of the bacteria at this time. The test solution was diluted batch by batch, and the inhibition and killing pairs of bacteria were calculated according to the comparison of four test targets: aqueous solution, paste cosmetics, powder cosmetics and liquid cosmetics. Results Under different sample concentration, the resident bacteria of skin were killed and inhibited. After multi-level calculation, the final killing pair value was higher, which could reach more than 7.5. Conclusion The inhibitory effect of increasing the concentration of preservatives on resident bacteria in the skin is basically in a positive change relationship. The higher the concentration of preservatives, the better the inhibitory effect will be formed; conversely, the lower the concentration of preservatives, the relatively poor inhibitory effect will be formed.