The MV Dixie Queen mock paddle steamer based at Butler's Wharf Pier is up for sale with offers in excess of £2.6 million sought.
Brought from Stockholm to the Thames a decade ago, the Dixie Queen is a replica 19th-century Mississippi paddle steamer.
Tower Bridge regularly lifts to allow the Dixie Queen, owned by Thames Luxury Charters, to pass into the Upper Pool of London.
"The Dixie Queen is an iconic boat which provides excellent facilities for dining and events," says Katie Wallace of Christie & Co's London bars and restaurants team.
"We expect interest from existing cruise businesses, plus bar and restaurant operators based in the UK and overseas.
"We believe the Dixie Queen will generate a high level of interest from a number of 'captains' looking to drop anchor on this unique opportunity."
The boat is currently licensed for 675 people while cruising and has sufficient capacity for 1,000 when moored.
There are two bar and dining areas; one seating 318 and another 170, plus external deck areas. With a fully-equipped commercial kitchen, the Dixie Queen is able to offer a full range of catering from buffet to fine dining.