| Clubname: | C.F. Os Marialvas |
| Fullname: | Clube Futebol Os Marialvas |
| Founded: | 1931[1] |
| Ground: | Complexo Desportivo de Cantanhede |
| Capacity: | ≈600 |
| League: | Honra B AF Coimbra |
| Season: | 2020–21 |
| Position: | 2nd |
Clube Futebol Os Marialvas is a Portuguese sports club from Cantanhede.
The men's football team plays in the Honra B AF Coimbra. The team played on the second tier of Portuguese football until the 1989–90 Segunda Divisão, then the 1990–91 Segunda Divisão B followed by a stint in the Terceira Divisão until 1998–99. Another stint in the Terceira Divisão was confined to the 2005–06 edition.[1] In the Taça de Portugal, Marialvas among others reached the fourth round in the 1992–93 edition.