Abstract: Objective Six M-H media were compared for selecting the best M-H in the sulfomides antimicrobialtest. Methods According to NCCLS, paper disks diffusion method were adopetd, 3 standard strains for E. faecalis(ATCC 229212), E.coli(ATCC 25922) and S. aureus(ATCC 25923) each were used to test SMZco 50 times on six M-H media;10 test strains each were used to test SMZco 10 times on six M-H media. Results 50 times inhibitory zone diameters＞20 mm when E. faecalis(ATCC 29212) were tested to SMZco by using Difco and Oxoid company M-H media, 50 times inhibitory zone diameters＜20 mm when other four M-H media were used. All test results in NCCLS limits when using E.coli (ATCC 25922) and S.aureus(ATCC 25923) to test SMZco on six M-H media. When 10 test strains were used to test SMZco zone diameters, other four M-H media possess different degree double ring phenomena except for Difco and Oxoid company M-H media. Conclusion Difco and Oxoid company M-H media are qualified, other four M-H media are not qualified.