Wolff River () is a short river in northern Fiordland, New Zealand. It rises near Mount Sutherland and flows westward to Madagascar Beach, between Martins Bay and Milford Sound / Piopiotahi.
The river was named in memory of a gold prospector, Carl Wolff. Wolff prospected for gold near the river mouth from 1885 to 1887. He drowned in the wreck of the Try Again at Martins Bay in 1887.