Former Wimbledon finalist Milos Raonic says Queen's is the "best way to prepare" for the All England Club after signing up to play this year's event.
Three-time Grand Slam champion Stan Wawrinka and 2014 Queen's winner Grigor Dimitrov have also been confirmed.
"We are excited about the line-up of established champions and talented young players we have assembled," said tournament director Stephen Farrow.
The Fever-Tree Championships take place at Queen's from 17-23 June.
British number one Kyle Edmund, Australia's Nick Kyrgios and Greece's Stefanos Tsitsipas, plus Canadian youngsters Denis Shapovalov and Felix Auger-Aliassime, are also set to be among a strong field.
Former world number one Andy Murray has a career-long commitment to the ATP 500 event, but is recovering from hip surgery.
BBC Sport will have live coverage from the west London club across television, radio and online.
Wimbledon starts at the All England Club a fortnight later on 1 July.
Farrow added he expected "more big names to be revealed" when the entry list is finalised next month.
Meanwhile, Great Britain will play the United States in a new junior team competition named in honour of former British Davis Cup captain Paul Hutchins, who died last month.
The Paul Hutchins Trophy, which will become an annual event, will be played on 21 and 22 June, with four junior players from each nation representing their respective countries.