| Marcial de Mello Castro | |
| Birth Date: | 3 June 1941 |
| Birth Place: | Tupaciguara, Brazil |
| Nationalteam1: | Brazil |
| Nationalyears1: | 1963 |
| Nationalcaps1: | 6 |
| Nationalgoals1: | 0 |
Marcial de Mello Castro (3 June 1941 - 2 August 2018) was a Brazilian footballer. He played in six matches for the Brazil national football team in 1963.[1] He was also part of Brazil's squad for the 1963 South American Championship.[2]