Two types of cloud water collectors were developed, and the devices were used to collect samples around the Hawaii Islands. The chemical analyses of cloud water showed that Na+, Cl-, and SO4= ion concentrations were approximately 10-4m; NH4+,NO3-, and Ca++ were 1 order of magnitude lower. The pH values were in the range of 4--5 regardless of sampling locations. The high acidity of cloud water over Hawaii may originate in the ocean or from long-range transport of anthropogenic pollution, in addition to local pollution, if present.