On 35 minutes, Son reacted quickest to Andre Onana’s parry of a Kin Jin-su effort to head home a true poacher’s goal.
It followed a superb hat-trick off the bench against Leicester after he was dropped from Antonio Conte’s line-up having failed to score all season until that point.
Tottenham face Arsenal at Emirates Stadium on Saturday lunchtime with Son now set to dart back to England for the north London derby.
— theKFA (@theKFA) September 27, 2022
Conte is set to reinstall him to the starting XI ahead of a hectic schedule in the lead-up to the World Cup.
Korea took a 1-0 victory with it Son who carried the main threat against the visitors. It was from his deep cross in the fifth minute that the Koreans almost took the lead, Kim Jin-su nodding back across goal before Onana kept out Jeong Woo-yeong's close range header.
Moumi Ngamaleu fired over the bar with a first-time effort from distance before the Koreans went in front 10 minutes from the interval. Cameroon narrowly missed out on an equaliser in the dying seconds of the half when a strike from Brentford’s Brian Mbeumo from distance was deflected onto the crossbar.
Son went close to claiming a second late in the game with a free kick that narrowly cleared the crossbar while Leandre Tawamba could have earned Cameroon a late draw, but his attempt to lob Kim Seung-gyu was too weak to clear the goalkeeper.
The Koreans, who will be appearing at their 10th consecutive World Cup, will face Ghana, Uruguay and Portugal in Qatar.
Additional reporting by Reuters.