
It is one of a trove of artworks secreted away for decades by Gurlitt in his Munich apartment.
The large scale oil is the first work from the collection to be put on sale.
Last month it became one of the first works to have been successfully restituted to the heirs of the original owners.
Gurlitt, who died in May 2014 aged 81, had a stash of 1,280 works of art hidden in his Munich apartment. They included pieces by Picasso, Chagall and Matisse.
The paintings were seized by the authorities in 2012 during a search of his home as part of a tax evasion probe.
Gurlitt inherited the priceless collection from his father Hildebrand, an art dealer who traded in works confiscated by the Nazis.
Before his death, Gurlitt had agreed to co-operate with the German authorities on establishing the paintings' provenance, and return them if they were shown to be stolen.
Two Riders on a Beach had been hung on a wall in the Munich apartment, and, according to Sotheby's, was "evidently much admired by Gurlitt".

David Toren, Friedmann's great nephew, is the only living heir to have seen the painting hanging in his great uncle's collection before it was seized by the Nazis in 1938.
Friedmann, having lost his properties and art works under the Nazis, died in 1942 of natural causes. His only child, Charlotte, died in Auschwitz the same year.
Toren managed to escape on a Kindertransport leaving Germany and grew up in Sweden before moving to New York where he lives now.
Commenting on the sale of the work, Toren said: "I am 90 years old now and blind, so while the return of the painting after so many years is of huge personal significance, I can no longer appreciate the painting as I did all those years ago in my great uncle's home.
"Though I am the only living heir to have seen the painting in my great uncle's home, I am one of a number of heirs and we have decided to sell. The painting can now pass into a new phase of its story."
Two Riders on a Beach will be exhibited to the public for the first time in more than 50 years when it goes on view in London on 19 June at Sotheby's. ?BBC