Hearns, who used the nickname "Hitman", compiled an amateur record of 155 wins and eight defeats and retired with a professional record of 61-5-1 with 48 knockouts.
He won five "world" titles and was the first boxer to win titles in four weight divisions.
Roach trains Filipino superstar Manny Pacquiao, among numerous other current and former world champions.
"I'd like to thank everyone, from the bottom of my heart, who voted for me and congratulate those inducted with me today," Roach said on New York on Tuesday.
"I started my career in professional boxing with Eddie Futch and now we will be together, forever, enshrined in the International Boxing Hall of Fame with the greatest legends of the sport. I am truly honoured and humbled."
Also selected were: Mark Johnson, a two-division champion, ring announcer Michael Buffer, broadcaster Al Bernstein and journalist Michael Katz.
Posthumous honourees are Cocoa Kid, Newsboy Brown, Leo Houck and Jake Kilrain in the old-timer category, promoters Hugh McIntosh and Rip Valenti in the non-participant category, and James Wharton in the pioneer category.
The inductees were selected by a panel of international boxing historians and writers. Induction day is June 10, 2012.