The Tekapo River flows through the Mackenzie Basin, Canterbury, in New Zealand's South Island.

Originally, the river flowed southwest for 50 kilometres from the southern end of Lake Tekapo before joining with the Pukaki River and flowing into the northern end of Lake Benmore. However, the water from Lake Tekapo is now diverted via a canal to Lake Pukaki as part of the Waitaki Hydroelectric scheme. These lakes are used to store water, and occasionally during a particularly heavy snow melt or if the power stations or canal need servicing, water may be spilt from either the dam or canal back into the riverbed. These events are much anticipated by kayakers, to the extent that they have been known to re-shape parts of the riverbed to create 'better' rapids.