In Mentawa areas there are indications that the U mineralization associated with tourmaline, quartz, sulfide minerals that fill the fracture aperture, on the rocks metasilt, and filit with the direction of WNW-ESE, the thickness milimetric-centrimetic with radioactivity 500-15000 c/s SPP 2 NF. The purpose of this study is to know the characters, parageneses and the process of formation of uranium minerals. The method used by microscopic observation of several examples of thin sections and polished sections of the previous research results. The study shows that uranium minerals are uraninite, associated with molybdenite, magnetite, rutile, ilmenite, pyrite, pyrrhotite, tourmaline, garnet, quartz and mineral pikblende associated with arsenopyrite, covelite, hematite, chalcopyrite, pyrite, pyrrhotite, tourmaline, quartz fill in cracks in rocks biotite and biotite schist. Mineral associations indicate that the process of formation of uranium mineralization occurs in three phases: pegmatik pneumatolitik, and hydrothermal alteration.