We investigated the availability, preference, and consumption of indigenous forest foods in Uluguru North (UNM) and West Usambara Mountains (WUM) of Tanzania. Data collection techniques involved focus group discussion, structured questionnaires, and botanical identification. Results revealed (1) there were 114 indigenous forest food plant species representing 57 families used by communities living adjacent to the two mountains; (2) sixty-seven species supplied edible fruits, nuts and seeds: 24 and 14 species came from WUM and UNM, respectively, while 29 came from both study areas; (3) of the 57 identified vegetable species, 22 were found in WUM only, 13 in UNM only, and 12 in both areas; (4) there were three species of edible mushrooms and five species of roots and tubers; (5) unlike the indigenous roots and tubers, the preference and consumption of indigenous vegetables, nuts, and seeds/oils was higher than exotic species in both study areas; and (6) UNM had more indigenous fruits compared to WUM, although preference and consumption was higher in WUM. We recommend increased research attention on forest foods to quantify their contribution to household food security and ensure their sustainability.