The presence of metallic ions in raw freshwater is a problem that occurs with greater intensity in periods of drought, due to the intensification of water withdrawal from lower levels of the dams, where there is a higher percentage of organic matter and concentration of metallic ions, including manganese and iron. High levels of these dissolved metals, in addition to altering the organoleptic properties of water, also cause deleterious effects on human and animal health. Given this, the present study aimed to evaluate the use of reverse osmosis in the removal of Mn+2 and Fe+2 from raw freshwater, to comply with the MS 5/2017 regulation (Brazilian standard), which establishes the maximum allowable values for Mn+2 and Fe+2 ions in drinking water. Three synthetic feed solutions were evaluated to study the retention alone and together of the metals, as well as the water permeability before and after the retention tests with each studied solution. The results showed that the reverse osmosis process retained 99 % of Mn+2, 93 % of Fe+2, and 98 % of the two ions together. Regarding the cleaning process, it increased the water permeability of the membrane after exposure to Fe+2 and the mixture of Mn+2 and Fe+2, being reduced after exposure to Mn+2 only. For the three types of feed, the post-cleaning fouling was estimated at 9.14 − 13.65 % in terms of permeability. Thus, reverse osmosis can be considered a promising process for the treatment of drinking water, and further studies are needed to implement this process in water treatment plants.