Simon de Pierrepont, Count of Roucy

Simon de Pierrepont (c. 1325–18 February 1392), count of Braine, was the youngest of the five sons of Count John V of Roucy and Marguerite de Beaumetz. When his father was killed at Crécy in 1346, Simon inherited Braine with its attached lordships.

In 1381 his childless niece Isabelle sold the county of Roucy to Louis of Anjou, the French king's brother. Louis died in September 1384, and Simon, by then the eldest of the house, contested the sale by claiming the right of lineage redemption.

The Parlement ruled for him, and by a treaty of 1385 he compensated Louis's heirs and took Roucy back, uniting it with Braine. He died at Bois-lez-Roucy, leaving by Marie de Châtillon a son, Hugh II, who succeeded him.