The 42-year-old actor picked up the accolade after a touching tribute from his 'Batman V Superman' co-star Amy Adams which praised him for the work he has done for the Eastern Congo Initiative, which he founded in 2010.
Ben said: "I've been called a lot of things in my life but I'm not sure that 'humanitarian,' until recently, has been one of them.
"It's something I've had a hard time accepting. I've had the privilege of working alongside so many incredible people in the Congo and all over the world who, I assure you, are far more deserving."
As well as the humanitarian accolade, Ben also saw his movie 'Gone Girl' scoop the Favorite Thriller Movie prize at the Nokia Theater in Los Angeles.
Elsewhere at the ceremony - which was hosted by 'Mom' stars Anna Faris and Allison Janney - Shailene Woodley picked up two prizes, sharing Favorite Movie Duo with her 'Divergent' co-star Theo James and having 'A Fault In Our Stars' named Favorite Dramatic Movie.
In the TV category, 'The Big Bang Theory' was the big winner, picking up both Favorite TV Show and Favorite Network Comedy, while its star Kaley Cuoco-Sweeting was named Favorite Comedic TV Actress.
In the music categories, Taylor Swift picked up three prizes and her friend Ed Sheeran was honored with two.
The 'Blank Space' star took home Favorite Female Artist, Favorite Pop Artist and Favorite Song for 'Shake It Off', while the British singer was named Favorite Male Artist and picked up Favorite Album for 'x'.
People's Choice Awards 2015 List of Winners:
Favorite Movie: 'Maleficent'
Favorite Movie Actor: Robert Downey Jr.
Favorite Movie Actress: Jennifer Lawrence
Favorite Movie Duo: Shailene Woodley & Theo James, Divergent
Favorite Action Movie: 'Divergent'
Favorite Action Movie Actor: Chris Evans
Favorite Action Movie Actress: Jennifer Lawrence
Favorite Comedic Movie: '22 Jump Street'
Favorite Comedic Movie Actor: Adam Sandler
Favorite Comedic Movie Actress: Melissa McCarthy
Favorite Dramatic Movie: 'The Fault in Our Stars'
Favorite Dramatic Movie Actor: Robert Downey Jr.
Favorite Dramatic Movie Actress: Chloë Grace Moretz
Favorite Family Movie: 'Maleficent'
Favorite Thriller Movie: 'Gone Girl'
Favorite TV Icon: Betty White
Favorite TV Show: 'The Big Bang Theory'
Favorite Network TV Comedy: 'The Big Bang Theory'
Favorite Comedic TV Actor: Chris Colfer
Favorite Comedic TV Actress: Kaley Cuoco-Sweeting
Favorite Network TV Drama: 'Grey's Anatomy'
Favorite Dramatic TV Actor: 'Patrick Dempsey'
Favorite Dramatic TV Actress: Ellen Pompeo
Favorite Cable TV Comedy: 'Melissa & Joey'
Favorite Cable TV Drama: 'Pretty Little Liars'
Favorite Cable TV Actor: Matt Bomer
Favorite Cable TV Actress: Angie Harmon
Favorite TV Crime Drama: 'Castle'
Favorite Crime Drama TV Actor: Nathan Fillion
Favorite Crime Drama TV Actress: Stana Katic
Favorite Network Sci-Fi/Fantasy TV Show: 'Beauty and the Beast'
Favorite Cable Sci-Fi/Fantasy TV Show: 'Outlander'
Favorite Sci-Fi/Fantasy TV Actor: Misha Collins
Favorite Sci-Fi/Fantasy TV Actress: Kristin Kreuk
Favorite Competition TV Show: T'he Voice'
Favorite Daytime TV Host: Ellen DeGeneres
Favorite Late Night Talk Show Host: Jimmy Fallon
Favorite Dramedy: 'Orange Is the New Black'
Favorite TV Duo: Nina Dobrev & Ian Somerhalder
Favorite TV Character We Miss Most: Sandra Oh as Cristina Yang, 'Grey's Anatomy'
Favorite Actor In A New TV Series: David Tennant
Favorite Actress In A New TV Series: Viola Davis
Favorite Sketch Comedy TV Show: 'Saturday Night Live'
Favorite Animated TV Show: 'The Simpsons'
Favorite New TV Comedy: 'Jane the Virgin'
Favorite New TV Drama: 'The Flash'
Favorite Male Artist: Ed Sheeran
Favorite Female Artist: Taylor Swift
Favorite Group: Maroon 5
Favorite Breakout Artist: 5 Seconds of Summer
Favorite Male Country Artist: Hunter Hayes
Favorite Female Country Artist: Carrie Underwood
Favorite Country Group: Lady Antebellum
Favorite Pop Artist: Taylor Swift
Favorite Hip-Hop Artist: Iggy Azalea
Favorite R&B Artist: Pharrell Williams
Favorite Album: 'x', Ed Sheeran
Favorite Song: 'Shake It Off', Taylor Swift