The Tapanui Branch was a railway line located near the border of the regions of Southland and Otago, New Zealand. Although the name suggests that it terminated in Tapanui, its furthest terminus was actually in Edievale. Construction of the line began in 1878 with the first section opened in 1880, and it operated until 1978, when it was destroyed by flooding from the Pomahaka River.

Tapanui is a small town in West Otago in New Zealand's South Island, close to the boundary with Southland region.