Vibrio parahaemolyticus was investigated for analysis of distribution and antibiotic susceptibility at the markets, Seoul in 2004. The average isolation rate was 26.8%(306/1,143) and the highest rate with 64.9% was obtained in August. The isolation rates from December to April was 0.0%. It is more effective to inoculate into the enrichment medium, alkaline pepton water by swabbing a sample with a cotton ball rather than pouring mixed sample. The isolation rates were from 24.4% to 37.1% in domestic samples and from 9.8% to 26.8% in imported ones. All of the isolates were resistent to ampicillin and ticarcillin and most of them were sensitive to chloramphenicol, tetracycline, nalidixic acid, amoxicillin, ceftriaxone, streptomycin, kanamycin, trimethoprim/sulfamethoxazol, ampicillin/sulbactam, ciprofloxacin.