- Born on March 23, 1701 in Nostang
- Deceased on December 6, 1762 in Pleucadeuc, at château de Lieuzel, at the age of 61 years
Parents
- Pierre Hyacinthe de Cosnoal (c. 1671 - 1741), seigneur de Saint-Georges
- Marie Anne Gabrielle de Guer ( - 1754)
Family
- Married on February 2, 1733 in Montbert, with Françoise-Renée Charette de Montbert (1716 - 1774), issuing
Anne Marie- Hyacinthe Gabrielle (1736 - 1764)
- Louise (1744 - 1790)