The 43-year-old fighter turned politician stepped away from boxing to launch a bid for the Philippine presidency that failed. He also served as a senator between 2016 and May this year.
On Sunday Pacquiao fought D.K. Yoo in a showcase match on the outskirts of the South Korean capital to raise money for Ukraine and homeless Filipinos.
Dressed in a shiny red robe with gold trimming, Pacquiao emerged into the KINTEX arena in Goyang to roars of excitement from the crowd.
For his opponent Yoo, a martial artist and internet star, it was only the second time in a boxing ring -- his previous encounter an exhibition match against former UFC fighter Bradley Scott.
Yoo, dubbed the "Korean Bruce Lee" in his homeland -- was no match for Pacquiao despite being significantly taller and heavier.
The South Korean was visibly tired and winded after the second round as a speedy Pacquiao moved in with an explosion of rapid-fire punches.
Pacquiao, who turns 44 next week, was the winner by unanimous decision and hinted that more appearances in the ring could lie ahead.
In a television interview, he said he would continue training to get back in shape. When asked about the prospect of a fight in 2023, he replied: "You'll see."
He had suggested prior to the match that he may not be done with fighting, calling Sunday's bout a "very good stepping stone to come back".
"This is a great opportunity to come back in the ring," he added. "I thought it was easy to retire... I really missed boxing."
Pacquiao, a multiple world champion who hung up his gloves with a 62-8-2 record after winning 12 major titles in eight weight classes, admitted: "I felt lonely when I retired from boxing."