Parc Hamelin Oberthür, Urban park in Rennes, France.

Parc Hamelin Oberthür is a 3.1-hectare botanical garden in eastern Rennes, laid out as a rectangle about 200 m long and 100 m wide. At its centre lies a pond of 2,762 m², bordered by 17,373 m² of lawn and 5,217 m² of wooded ground. A massive cedar stands on the far bank, and the two hôtels particuliers linked by a porch face the rue de Paris to the north.

François-Charles Oberthür began buying land in the faubourg de Paris in 1852, and the park was laid out by landscape architect Denis Bühler in 1863–1864. It was enlarged by about 2 hectares in 1882. In 1953 part of the grounds was sold off for housing, creating rue René Marcille and reducing the park from 4.9 to 3.1 hectares. The City of Rennes acquired it in 1960 and opened it to the public on 27 May 1977.

The park is named after the Oberthür family, notably François-Charles Oberthür and his wife Marie Hamelin. From 1887 the printing works' brass band and gymnastics society performed here. Today it hosts local events; in 1982 it held the 'Rennes-Sculpture' exhibition, including works by Francis Pellerin.

The park offers four entry points from different streets: rue de Paris, boulevard Jeanne d'Arc, square Roland Garros, and rue René Marcille. Multiple pathways allow you to explore the grounds on foot at a relaxed pace.

The bald cypress in the park grows aerial roots, called pneumatophores, that let it breathe above the water. The pond was regularly stocked with fish and now holds many carp, alongside ducks, turtles and a grey heron that visits. A giant sequoia stands near the northern side.