The TV veteran, who will quit CNN's Larry King Live later this year (10), became the star guest as business tycoon Trump stepped in to interview the newsman about his 25-year stint on the show.
A slew of King's former interviewees, including Al Pacino, Quentin Tarantino and Snoop Dogg, also paid tribute to the legendary TV host and asked their own probing questions in special video messages.
Opening the show, Trump told the audience, "I'm Donald Trump and I'm turning the tables on Larry on his 25th anniversary at CNN."
He then asked King to name his favourite ever guest - and the interviewer picked iconic actor Marlon Brando.
King revealed, "If I had to pick one - well, there's so many. It would probably be Brando... He entertained the entire crew. He was sweet. He was funny. At the end of the interview, he kissed me. He was responsive. He was an incredible guest. I never forgot Marlon Brando."
A string of celebrities also picked the 1994 Brando interview as the show's most memorable, thanks to the infamous smooch.
Filmmaker Michael Moore and actor Sean Penn both pinpointed the Brando clip, while Glee's Matthew Morrison said in a video message, "My favourite Larry King memory was when Marlon Brando kissed him on the lips. Leaned over and gave him a big old smooch."
During the show, Celine Dion, Pamela Anderson, Aretha Franklin, Hilary Clinton and Betty White all gave video tributes, while Johnny Depp, Anne Hathaway and former U.S. vice president Al Gore made jokes about King's love of suspenders (braces).
Tarantino asked King who his sexiest ever female star guest was, to which he replied Charlize Theron, while Lionel Richie praised King's coverage of the 9/11 terrorist attacks in 2001.
As the show drew to an end, Pacino gave a touching anniversary message, saying, "Hi, Larry. It's me, Al, and I am here to congratulate you on your 25 years of working for CNN, Larry KIng Live. You still have the same energy, the same commitment, the same interest in other people and what they think and how they are feeling and what they got to say, and I think that is pretty amazing. So congratulations from me to you."
And King was delighted with the special edition show, telling Trump at the end: "Thanks for everything. I will never forget this, Donald."