Martín was the son of Alonso Fernandez Portocarrero and Francisca Sarmiento. The date and place of his birth have not been found.
His wife was Leonor Cabeza de Vaca. They were married, but the date and place have not been found. Their three known children were Beatriz (?-?), Pedro Fernández (?-?) and Francisca (?-?).
| Attribute | Date | Description | Details | Source | Multimedia | Notes |
|---|---|---|---|---|---|---|
| Nobility Title | señor de Moguer 4° |