Glenn Donald McGrath AO (/məˈɡrɑː/; born 9 February 1970) is an Australian former international cricketer whose career spanned 14 years. He was a fast-medium pace bowler and is considered one of cricket's greatest bowlers and a leading contributor to Australia's domination of world cricket from the mid-1990s to the late 2000s. McGrath was a member of the Australian team that won three consecutive World Cup trophies, winning the 1999 Cricket World Cup, the 2003 Cricket World Cup, and the 2007 Cricket World Cup. In the 2003 final, he took the winning wicket of Zaheer Khan. McGrath was also a member of the team that won the 2006 ICC Champions Trophy.

Known throughout his career for maintaining an accurate line and length, McGrath displayed a consistency that enabled him to be one of the most economical and successful fast bowlers of his time. In terms of total career Test wickets taken by fast bowlers, McGrath is the third-most successful of all fast bowlers, behind James Anderson and Stuart Broad. On the list of all Test bowlers, he is sixth, and no bowler has taken more wickets at a lower average. He has also taken the seventh-highest number of one day international wickets (381) and holds the record for most wickets (71) in the Cricket World Cup. McGrath announced his retirement from Test cricket on 23 December 2006, with his Test career coming to an end after the fifth Ashes Test in Sydney in January 2007, while the 2007 World Cup, which marked the end of his one-day career, saw him win the man-of-the-tournament award for his outstanding bowling, which was instrumental in Australia winning the tournament.

McGrath later played for the Indian Premier League team of the Delhi DareDevils and was one of the competition's most economical bowlers during its first season.

McGrath is the director of MRF Pace Foundation, Chennai, replacing Dennis Lillee, who served for 25 years. He currently serves as president of the McGrath Foundation, a breast cancer support and education charity he founded with his late first wife, Jane.

McGrath was honoured during the seventh annual Bradman Awards in Sydney on 1 November 2012. He was inducted into the ICC Cricket Hall of Fame in January 2013.

McGrath was born in Dubbo to Beverly and Kevin McGrath. He grew up in Narromine, New South Wales (NSW), where he first played cricket, and his potential was spotted by Doug Walters. He moved to Sydney to play grade cricket for Sutherland and made his debut for NSW during the 1992–93 season. McGrath capped his rapid rise in the next Australian summer with selection in the Test team after only eight first-class matches.

McGrath's Test debut was against New Zealand at Perth in 1993–1994. In Australia's 1995 Test series victory McGrath took the approach of bouncing the West Indies team, including the bowlers, which had not happened before. In McGrath's biography, Ricky Ponting is quoted as saying:

I remember thinking Glenn's decision to take on the West Indies bowlers sent out a positive message to the West Indies that the Australian side was really up for it. Ambrose, Walsh, Kenny Benjamin had never been treated like that before. It made the West Indies sit back and think, 'This Australian team is fair dinkum—they're really up for it.' Even if you aren't the murder boys of cricket, you can show little things to let the opposition know you are serious. It might be the way you warm up, how you dress to go to the ground. Perception can be enormous. If you can give off the right signals to (a) bluffing them or (b) showing them what you're all about. McGrath, at that stage of his career, showed them what he was all about. His body language and the way he looked at their batsman—the wry smile—it sent a signal to the batsman and his own team-mates that he knew what he was doing.