The event, which starts today in Normandy and runs until September 7, features competitors from 74 countries with around 1,000 riders taking part.
An audience in the region of 500,000 is expected to watch proceedings.
Snoozebox said its hotel will be at the Haras National du Pin for the eventing discipline and will be mainly used by riders. Zara Phillips is among the competitors in the eventing discipline.
Lorcan O Murchu, Snoozebox chief executive, said: "We are delighted to partner with the premier global equestrian event.
"Snoozebox brings a track record to the World Equestrian Games of delivering hotel accommodation solutions at international sporting events such as London 2012 Olympic Games and the Queen's Diamond Jubilee."
Fabien Grobon, chief executive of the Alltech FEI World Equestrian Games, added: "With Snoozebox we can create a bespoke hotel with good quality accommodation, exactly where we need it. An on-site hotel enables participants to be within easy access of the stables, arenas and facilities throughout the Games."
AIM-listed Snoozebox, which has former racing driver David Coulthard as its president, provided one of its hotels in Glasgow during the Commonwealth Games and has had one in Edinburgh for the duration of the Fringe festival.
At the Ryder Cup in Gleneagles, Snoozebox will operate a hotel for host broadcaster European Tour Productions.