William Peter O'Rourke (উইলিয়াম পিটার ও'রুর্ক) is a New Zealand cricketer. A right-arm fast bowler, he plays for the Canterbury cricket team in domestic cricket. He made his international debut for New Zealand in December 2023, having previously played for the national under-19 side.

O'Rourke was born at Kingston upon Thames in London in 2001. His father, Paddy O'Rourke, played as a fast bowler for Wellington between the 1989–90 and 1991–92 seasons and his uncle, Matthew O'Rourke, played a single senior match for Auckland in 1991–92. The family had moved to England before O'Rourke's birth and, when he was around five years old, moved back to New Zealand, settling in Auckland. He played cricket from a young age and made appearances for Auckland age-group sides from the 2017–18 season until 2019–20 before moving to the South Island to study at the University of Canterbury.

In December 2019, O'Rourke was named in New Zealand's squad for the 2020 Under-19 Cricket World Cup. After impressing for his club side Burnside West Christchurch University Cricket Club, he was called into the Canterbury 'A' team during the 2020–21 season, taking 10 wickets for the side during the National Provincial A Tournament. In January 2021, he played two Twenty20 matches for a New Zealand XI against the touring Pakistan Shaheens.

In March 2023, O'Rourke was named in the New Zealand A squad for their first-class series against Australia A and in December 2023 he was called-up to the New Zealand squad for the first time ahead of a One Day International (ODI) series against Bangladesh. He made his ODI debut during the series, becoming the first England-born cricketer to play for New Zealand since Roger Twose in the 1990s.

The following month, O'Rourke was called into New Zealand's Test squad for their series against South Africa. He made his Test debut on 13 February 2024 in the second match of the series, taking a five-wicket haul in South Africa's second innings and finishing the match with figures of nine wickets for 93 runs (9/93), recording the best match-bowling figures by a New Zealander on Test debut.

O'Rourke is known for his ability to generate extra bounce from his tall frame. A fast bowler who can reach delivery speeds of 150 kilometres per hour (93 mph), his bowling style has been compared to that of Kyle Jamieson, another tall New Zealand fast bowler; O'Rourke has spent time working alongside Jamieson to develop his approach to bowling.