Boterdiep (Gronings: Botterdaip; translation: Butter Deep) is a canal in the Province of Groningen in the Netherlands.

It used to have its source in the centre of Groningen, but it has been rerouted to the Van Starkenborghkanaal [nl].

In the 15th century, the Cleisloot provided a connection to Bedum north of the city of Groningen.

[2] In the early 20th century, the van Starkenborghkanaal [nl] was dug, and in 1912, the Boterdiep was re-routed to the new canal.

[7] The Boterdiep is nowadays mainly used for recreational boating and a 6 km/h speed limit applies.