Labuschagne had initially signed a two-year deal that encompassed both the 2020 and 2021 seasons but with the current campaign delayed by the coronavirus, it has been agreed that he won’t return to Cardiff this term.
“It was an easy decision to extend my contract for another year and commit to Glamorgan and Wales long term,” Labuschagne, 25, told Glamorgan’s website.
“I was gutted not to be returning to Glamorgan for the 2020 season after I loved my first year here, so I’m delighted to be recommitting myself to the club for the next couple of years.
“I loved my first year at the club and the dressing-room environment and I’m looking forward to playing cricket with them again.”
Labuschagne scored 1,114 County Championship runs at an average of over 65 last season, including five centuries and five half-centuries.
His Glamorgan form helped him gain a place in Australia’s team for the 2019 Ashes series, during which he scored 353 runs at an average of 50.42 after becoming Test cricket’s first concussion substitute when he replaced star batsman Steve Smith at Lord’s.