It comes after a year of celebrating the city's cultural legacy and America's 250th anniversary.
"As Philadelphia continues to celebrate America's 250th anniversary, we continue to recognize the people, culture and accomplishments that have shaped our city and our nation," said Mayor Cherelle Parker.
On Thursday night, the duo got to sit back and watch their legacy of music sung and celebrated before thousands.
The concert celebrated 55 years of Philadelphia International Records, founded by Gamble and Huff in 1971, bringing artist like The Spinners, The Delfonics, The Three Degrees, The O'Jays , Jean Carne and Harold Melvin & the Blue Notes to international fame.
They created the iconic Sound of Philadelphia in the 1970s, which is a distinctive blend of soul, R&B, orchestration and socially conscious lyrics.
"Gamble and Huff wrote so many songs for us, I can't even name them," said Roger Banks, a member of Legendary Blue Notes featuring Sugar Bear. "They've been doing this since Mickey was a mouse. I'm glad to be a part of the legacy from Harold Melvin."
Kenny Gamble and Leon Huff say all they wanted was to create a 'message in their music' of love and empowerment. They say they are honored to be celebrated in their hometown.
Music pioneer Thom Bell was also honored.
"So often you hear of someone passing, getting sick; give them their flowers while they can see them," said WDAS radio personality Miss Patty Jackson. "They did so many signature songs!"