The Winschoterdiep is a Dutch-built canal which lies in Groningen, the Netherlands. It leads to the Ressel, which is actually part of this canal. Construction was started in 1618 and finished in 1634. The Winschoterdiep's total length is 35.5 kilometres, and it is approximately 100 metres in width. Sixteen bridges and locks are built across this canal, as well as many other passages. Ships must be less than 16 m in breadth to pass through some of these. It is one of the oldest canals ever built in Groningen still in use. In the section between Hoogezand and Waterhuizen, there are several shipwharfs. Near the canalHoogezand was also founded in 1618.
Where the canal runs through the municipality of Menterwolde, there is significant water-sport activity in season.