He plays for Sylhet Royals in the Bangladesh Premier League. Haque made his first-class debut during the 2008–09 season, against Chittagong Division. From the middle order, he scored 22 runs in the first innings in which he batted, and 2 not out in the second. Haque bowled four overs during the match, which finished as a draw as there was no play in the game's first two days.

During the Bangladesh Premier League, 2012, he won the Man of the Match award for scoring 53* off 28 balls for his team Barisal Burners against the Khulna Royal Bengals to guide his team to a 4 wicket victory,

In 2013–14 He along with Roshen Silva set the highest 4th wicket partnership in List A history of 276 runs.

Mominul captained Bangladesh A team for the tour of India in late September 2015. It was his first tour abroad as a captain.

He made his test debut against Sri Lanka on 8 March 2013 at Galle, Sri Lanka. He scored a half century on his debut and ended up scoring 156 runs in 3 innings at an impressive average of 52.00 in his maiden test series.

He made his first century in a Test match against New Zealand in Chittagong in 2013, off just 100 balls. In the second Test of the series, Mominul scored another century, which was also a not out innings. With this feat, Mominul became only the second Bangladesh batsman after Tamim Iqbal to hit centuries in two consecutive Tests.

After a mammoth loss against Sri Lanka by an innings at home, Bangladesh came back strongly in the second Test courtesy of Mominul's hundred. Sri Lanka poster 587 runs for the first innings with the help of Sangakkara's triple century, Bangladesh scored 271 for reply, where Mominul again scored an unbeaten 100. It was his second Test century at the ZAC Stadium, Chittagong and the match was drawn at the end.

Against Zimbabwe on 15 November 2014, Mominul scored his fourth Test century, which is his third at ZAC Stadium to post 443 for Zimbabweans to chase. In this match, Bangladesh also scored 300-plus in both innings of the match, a first for Bangladesh in Test history as well. With his continuous form, Mominul joined the elite club of Everton Weekes, Alec Stewart, Matthew Hayden, Jacques Kallis, Simon Katich and Kumar Sangakkara as batsmen with 50-plus scores in nine consecutive Tests. He has also become the fourth batsman after Weekes, Sunil Gavaskar and Mark Taylor to score 50-plus eleven times in his first 12 Tests. Bangladesh comfortably won the match by 186 runs by achieving their first ever 3-0 Test-series whitewash. Mominul adjudged man of the match for his performances.

As of 20 May 2015, Mominul became the 5th batsman in cricket history to score 50 in at least one innings of a test match in 11 consecutive test matches, despite having played less than 15 test matches.^[8]

During the tour for New Zealand in early 2017, Mominul participated for the third highest partnership for any wicket for Bangladesh in New Zealand soil, when he along with Tamim added 85 runs. During the course, he scored a fifty.