Square Léon-Serpollet, Urban park in the 18th arrondissement, Paris, France.

Square Léon-Serpollet is a 15,800 m² terraced garden in the 18th arrondissement, laid out in 1991 and renovated in 2021–2022. Its sandy central area holds a red metal climbing frame, a black fence and a tall lamppost, with trees growing straight from the sand. Plantings include flowering cherries, pterocaryas, Byzantine hazels, hornbeams, maples, Siberian elms, Judas trees and Virginia tulip trees, plus a granite fountain basin.

Created in 1991 on the former site of Léon Serpollet's workshop, where the French inventor developed his steam generator system and tested steam-powered tricycles that would later break land speed records in 1902.

The park contains a memorial stele honoring Jewish children who died during deportation, serving as a place of remembrance and reflection for the local community in this historically diverse arrondissement.

Open year-round from 8:00 AM to 9:30 PM in summer and until 7:30 PM in winter, the park offers accessible pathways, children's playground equipment, ping-pong tables, and bicycle parking facilities.

The square holds the ÉcoJardin label, and a granite fountain decorates its pond. A glass stele commemorates young Jewish children of the 18th arrondissement murdered during the Second World War. The land was given to the City by Madame Marzak.