Chemical composition, hydrogen and oxygen isotopic ratios of precipitation were analyzed for studying water and atmospheric circulation. Precipitations were sampled in Wakayama prefecture at the south of Izumi mountains and also in Osaka prefecture at the north. Cl- in precipitation sampled at Wakayama, Osaka and Tondabayashi cities were mainly derived from sea. Concentrations of NO3- and SO42-derived from productions accompanied with city activities in Osaka and Tondabayashi cities were higher than those in Wakayama city. The average pH values, 5.2 in Osaka and Tondabayashi cities were lower than 5.8 in Wakayama city.δ D and δ 18O values in precipitation were very variable with times. In spite of the variation widely, time series of δ D values showed almost the same values in the wide areas (60km) from Wakayama to Osaka prefecture. Therefore, δ D and δ 180 values in precipitation were thought to depend on the change of δ D and δ 180 values in air.