In this paper, we present the design and evaluation of a prototype Autonomous Water Purifier (AWP) for removing heavy metals from contaminated water. The AWP prototype uses solar energy for its operation; the autonomous photovoltaic system is designed to operate up to 8 hours per day and to generate a water flow of 112 liters per day. The prototype was designed to remove biological and chemical agents. It was achieved the elimination of total coliforms, fecal coliforms, total alkalinity, total hardness, total solids, chloride and sulfate from 50 to 100%, as well as the removal of heavy metals.  The Pb2+, Hg2+, Cd2+ and Cu2+ were eliminated from 80 to 99%. This wide range of contaminant removal shows a unique way to treat contaminated water in comparison to existing purification systems. The prototype was evaluated with river and spring water from different rural communities of Chiapas, Mexico. The results indicate that the prototype is able to completely remove contaminants in natural waters and get water that meets the guidelines that mark the Mexican official standards. This work helps to solve problems in marginalized communities and natural disaster areas where they have no access to clean water, electricity and suffer from waterborne diseases