The Leekster Hoofddiep is a canal in the northern Netherlands that serves as a primary inflow to the Leekstermeer, the largest lake in the province of Drenthe. It connects the town of Leek and the Nienoord Estate area to the lake, running through agricultural and estate countryside in the border region of Drenthe and Groningen.

The waterway is well suited to human-powered craft. Canoes and stand-up paddleboards are both practical options, and the channel is also used by whisper boats and small motorboats. The Nienoord route, which departs from the Leekstermeer and follows the Leekster Hoofddiep toward Nienoord Estate and Leek's small harbour, takes approximately 1.5 hours by canoe or SUP. The route is described as suitable for shorter outings and passes through open countryside with views of the Nienoord Estate. Paddlers typically return via the same water. Boat and canoe rental, including SUP equipment, is available at Cnossen Leekstermeer on the lake, making the Leekster Hoofddiep accessible to visitors without their own equipment.

The broader Leekstermeer area has been a designated Ramsar Wetland since 2000, reflecting the ecological significance of the surrounding landscape. The lake into which the Leekster Hoofddiep drains covers 335 hectares and averages between 1 and 1.5 metres in depth.