Murray's brother, Jamie, has also confirmed that he will compete in the doubles at Queen's.
— Aegon Championships (@QueensTennis) February 23, 2017
Dimitrov won the tournament three years ago, a result that set him up for a run to the Wimbledon semifinals a few weeks later.
The Bulgarian beat Andy Murray in straight sets as he booked his place in the last four in SW19 three years ago, and he believes he has become a better player as he plots more success in west London.
Dimitrov said: "I feel like I'm a better player, a better person, better everything.
"The grass-court season is going to be a big thing for me with Queen's and then Wimbledon around the corner. I've seen the field, it's going to be very strong again, but I'm excited to see what my form is going to be like."