Bone Bolango is a regency that has a lot of ASGM sites that use elemental mercury for gold processing compare to the other regencies in Gorontalo province. This activity produces waste containing hazardous substances dumped in Bone River. This river has been used to support human life also a source of drinking water in the city of Gorontalo. This research aims to investigate the source of toxic metal in the human hair of Tulabolo ASGM sites in Bone Bolango Regency, Gorontalo Province, Indonesia. Hair samples were collected from the inhabitants who are living near Bone River. Total of toxic element concentration in the samples was analyzed by using Particle-induced X-ray emission (PIXE) which derives from Iwate Medical University. The maximum concentration of Hg, As, and Pb are 12.3 µg/g, 11.1 µg/g, and 13.5 µg/g, respectively. Those results show that Hg, As, and Pb are in danger level. Also, the results reveal that natural and anthropogenic sources have regionally polluted the areas.