Philippe of Dammartin (Philippa de Dammartin) was a 13th-century noble woman. Philippe was the daughter of Simon of Dammartin, Count of Aumâle and his wife Marie of Ponthieu.^[1] She was the sister of Joan, Countess of Ponthieu, wife of Ferdinand III of Castile and mother of Eleanor of Castile, the wife of Edward I of England.

Philippe married three times.
1. Her first marriage was to Raoul II of Lusignan in ca 1239/40. Philippe was his third wife.^[2] They had no children, but she was the stepmother of Marie de Lusignan.
2. Her second marriage was to Raoul II, Lord of Coucy in ca. 1246.^[2] They had one child:

• Enguerrand de Coucy, died young (before 1250).

3. Her third marriage was to Otto II, Count of Guelders between 1252 and 1254.^[3] They had four children:

• Reginald I, Count of Guelders.^[3]
• Philippa of Guelders, who married Waleran II, Lord of Valkenburg.
• Margaret of Guelders, who married Dietrich VII, Count of Cleves.
• Maria of Guelders.