De Grandhomme began his career by playing for Manicaland in Zimbabwe. He has played for the Auckland Aces in the State Championship since 2006. De Grandhomme played for Zimbabwe in the 2004 Under-19 Cricket World Cup in Bangladesh. In 2017, De Grandhomme joined Warwickshire. He was a major part of their success in the Natwest T20 Blast scoring 38 not out in the quarter final win against Surrey at The Oval.

In May 2018, he signed for Northern Districts ahead of the 2018–19 season, after playing for Auckland since 2007.

De Grandhomme made his international debut on 11 February 2012 in a Twenty20 International against Zimbabwe. His ODI debut came against South Africa on 3 March 2012 in which he made 36 off 36 balls before being run-out by Albie Morkel.

In November 2016 he was named in New Zealand's Test squad for the tour against Pakistan and debuted in the first Test match on 17 November. He took his maiden Test wicket by dismissing Azhar Ali. In the match, Grandhomme scored a fifty in the match and took a five-wicket haul in his maiden innings of Test match cricket. He won the Man of the Match award in his first test match and became fourth New Zealand player to do so.

On 2 December 2017, against the West Indies, de Grandhomme scored his first Test century. The 71-ball century recorded as the second-fastest century in Tests by a New Zealand batsman.^[6] He left the tour ahead of the ODI matches against the West Indies after his father died in Zimbabwe.^[7]

In May 2018, he was one of twenty players to be awarded a new contract for the 2018–19 season by New Zealand Cricket.^[8]

• List of New Zealand cricketers who have taken five-wicket hauls on Test debut
• List of Auckland representative cricketers