The antimicrobial activity of methanol extracts from 17 seaweeds was screened using a paper disc method and using three human skin pathogens: Staphylococcus aureus, S. epidermidis and Candia albicans. The serial extraction of Neorhodomela aculeata was also conducted using four different solvents (n-hexane, chloroform, ethyl acetate, and methanol) and the minimal inhibitory concentration (MIC) of each extract was examined for the three pathogens. Of the 17 seaweeds, the MeOH extracts of Ulva conglobata, N. aculeata and Symphyocladia latiuscula showed antimicrobial activities. For the extracts from N. aculeata and S. latiuscula, the inhibition zones were more than 10 mm in diameter against S. aureus and S. epidermidis, and >7mm for C. albicans. The inhibition zone of U. conglobata treatment was about 8 mm for S. aureus only. The MIC of each N. aculeata extract ranged from 8 to 32 mg/mL against the three human skin pathogens, and the lowest value (8 mg/mL was with the methanol extract. These results suggest that the MeOH extract of N. aculeata might be useful for developing new antibiotics against human skin pathogens.