Abstract: The paper researched the antimicrobial properties of extracts of Noni fruit, seed and leaf extract. By studying the antimicrobial properties of Noni fruit fermented juice, seed ethanol extract, seed steam distillate extract, Noni leaf extract and honeysuckle extract respectively on four kinds of pathogens as the target, Pseudomonas aeruginosa, Escherichia coli, Staphylococcus aureus, Streptococcus mutans, three kinds of extracts with stronger antimicrobial properties ( Noni fruit fermented juice, seed steam distillate extract and honeysuckle extract) were screened out.Through the experimental results from the single factor experiment and three factors three levels orthogonal experiments, the best formula of compound plant bacteriostatic liquid was optimized.The results showed that the antimicrobial effect of liquid mixed from 87% of the Noni fruit fermented juice, 8%of the distilled steam extract and 5% of the honeysuckle extract was the best.The inhibition zone diameters of different bacteria were 15 mm of Pseudomonas aeruginosa, 22 mm of Escherichia coli, 28 mm of Staphylococcus aureus, 17 mm of Streptococcus mutans.The compound plant bacteriostatic liquid has antimicrobial effect, and it provides theoretical basis for further developing antimicrobial product.