We analyzed water for landscape use in public parks in a local city. Water samples were collected from 6 sampling sites monthly. Averages were as follows: BOD 1.2~3.1 mg/L, pH 7.1~7.6, phosphate ion 0.04~0.31 mg/L, ammonium-N 0.04~0.11 mg/L, suspended solids 5~11 mg/L, coliform bacteria 0~283 CFU/mL and heterotrophic bacteria 200~12580 CFU/mL. Regionella species were detected from 3 (13%) out of 26 samples in 3 sampling sites at a range of 4 to 40 CFU/100mL. Regionella contamination suggested that water in public parks might be a potential source of Legionnaires' disease. There was no relationship between Regionella species and other water quality indices.