Kusal Mendis is one of the 15 players who have been named in the Sri Lanka squad to play the ICC Cricket World Cup 2019 in England and Wales. Kusal Mendis, who made his one-day international debut on 16-Jun-16, had played 62 ODI matches until the 2019 World Cup. In the 60 innings he batted in, he had scored a total of 1626 runs, having faced 1917 balls, at an average of 28.03 and a strike rate of 84.82. He was unbeaten in 2 of those innings. His highest score in an innings was 102. He had 1 centuries and 14 half-centuries to his name. In the bowling department, Kusal Mendis had bowled 20 balls and taken 0 wickets while conceding a total of 28 runs. 

Kusal Mendis is a professional Sri Lankan cricketer who plays for all forms of the game. He only played sixteen first-class matches before playing for the national side. He usually bats at number three in all formats. In November 2017, he was named the One Day International (ODI) batsman of the year for the 2016–17 season at Sri Lanka Cricket's annual awards. In April 2019, he was named in Sri Lanka's squad for the 2019 Cricket World Cup

He captained Sri Lanka's squad for the 2014 ICC Under-19 Cricket World Cup. He was the 132nd Test player for Sri Lanka, gaining his cap during the second Test of Sobers-Tissera Trophy. He made his Test debut in 2nd Test of West Indies tour of Sri Lanka 2015.
He made his One Day International (ODI) debut against Ireland on 16 June 2016, scoring his maiden ODI fifty. Mendis made his Twenty20 International (T20I) debut for Sri Lanka against England on 5 July 2016 in the same tour.
On 28 July 2016, Mendis scored his maiden Test century during the first Test against Australia at the Pallekele Cricket Stadium. He became the youngest Sri Lankan to score a century against Australia and also the highest score against Australia on home soil. Mendis won the Man of the Match award for his performance.
In the fifth match of the Tri-series in Zimbabwe against the West Indies, Mendis scored 94 runs. Sri Lanka posted 330 runs off 50 overs, which was recorded as the highest total by Sri Lanka against the West Indies. Mendis was adjudged man of the match for his batting. In the final, Mendis scored another fifty, guiding the team to win the series by 6 wickets. His all-round performances in the series gave him his first player of the series award.
On the first Test against Bangladesh at Galle, Mendis scored his second Test century, just fall short 6 runs for his double hundred. His score of 194, before he was caught by Tamim Iqbal.
On 28 March 2017, in the second ODI against Bangladesh at Rangiri Dambulla International Stadium, Mendis scored his maiden ODI century, with 102 runs. However, the match ended as a no result, due to heavy rain.
On 8 June 2017 against India in 2017 ICC Champions Trophy, Mendis scored a match-winning 89 runs to seal the match for Sri Lanka. In the match, Sri Lanka chased 321 runs scored by India, by recording the highest successful run chase in Champion's Trophy history. He along with Danushka Gunathilaka stood 159-run stand for the second wicket and helped to reach the mark. This was Sri Lanka's joint-highest chase, and their first successful 300-plus chase since the 2015 World Cup as well.
On 30 June 2017 against Zimbabwe, Mendis passed 1,000 ODI runs, becoming the joint second-fastest (with Tharanga) for Sri Lanka to achieve this.
Mendis was totally out of form during the 2018 Asia Cup, where he was dismissed for naught in both games against Bangladesh and Afghanistan. He was omitted from the England tour in Sri Lanka. He could not produce much runs from the bat for the next 24 innings.
During the first Test against Bangladesh in 2018, Mendis scored his fourth Test hundred. Mendis was dismissed for 196 runs, four runs short of his maiden double century just before the tea break.
After good performances in Tests against Bangladesh, Mendis was named to the T20I squad for Sri Lanka by replacing injured Kusal Perera. In the first match, he scored a match winning knock of 53 from 27 balls. The chase of 193 is recorded as the highest T20I chase by Sri Lanka as well. Mendis adjudged man of the match, which is his first in T20Is. In the second T20I, Mendis scored another match winning half century and Sri Lanka posted 210 in their 20 overs. Mendis was awarded with both man of the match and player of the series.
In May 2018, he was one of 33 cricketers to be awarded a national contract by Sri Lanka Cricket ahead of the 2018–19 season.