In April 2019, he was named in Sri Lanka's squad for the 2019 Cricket World Cup. After consecutive failures of 0,0, 9 with the bat in World Cup, Mathews regained his form during the pool match against England. He scored unbeaten 85 runs to post a total of 232. With the bowling performance by veteran Malinga, Sri Lanka won the match by 20 runs. During the match, Mathews scored his 12,000th international run for Sri Lanka. During the match against West Indies on 1 July 2019, Mathews surprisingly requested to bowl the 48th over. He picked up the wicket of Nicolas Pooran who was on 118, and was all set to take the West Indies to victory. Mathews, had not bowled for 8 months, even in the nets. On 6 July 2019 against India, Mathews scored his third century, where all his three centuries now came against India. However, Sri Lanka lost the match by 7 wickets.