The mixture of 40% ethyl alcohol, 0.1% chitosan and 100 ppm grapefruit seed extract(ECG solution) showed significant antimicrobial activity against Listeria monocytogenes, Bacillus subtilis, Bacillus cereus, Salmonella typhimurium, Pseudomonas fluorecens, Vibrio parahaemolyticus, Vibrio vulnificus and Shigella sonnei after treated with 30% or above concentration of ECG solution for 3 min at 20 o C. The tested microoganisms except Bacillus spp. were not detected after treated with 80% and 100% ECG solution for 3 min at 20 o C. The viable cell number of raw vegetable sprout decreased about 1.88, 2.08 and 2.30 log cycle compared with control after treated with 50% ECG solution for 1, 5 and 10 minute at 20, respectively. The microbial count of pork reduced about 1.63, 1.86 and 1.86 log cycle compared with control after treated with above mentioned conditon. The viable count of cuttlefish after treated with 50% ECG solution for 1 to 10 minutes reduced about 1 log cycle compared with control but didn`t decrease significantly as increase the treatment time.