Rainwater used for drinking purposes was tested in a water purification system. Most parameters were within the standard water quality. Microorganisms were detected when the rainwater was not treated with ultraviolet (UV-C) light. However, analysis of rainwater aftεr UV-C sterilisation showed no trace of microorganisms. The suspended matters in the rainwater were removed by the sand layer. Organic compounds and heavy metals were adsorbed by bamboo activated carbon and chitosan bead. The rainwater using water purification system appear to provide drinking water of relatively good quality compared with surface water and groundwater.