Ervine intends to return to Britain and has been replaced by Tinotenda Mawoyo.
Harare: All-rounder Sean Ervine pulled out of Zimbabwe's squad for personal reasons on Wednesday, dealing the team's World Cup hopes a major blow.
Ervine quit English County side Hampshire two weeks ago to play for Zimbabwe for the first time in seven years but he intended to return to Britain. His younger brother Craig remained in the World Cup squad.
Sean Ervine was replaced by Tinotenda Mawoyo, an opening batsman and wicketkeeper who received two one-day international caps against Bangladesh in 2006.
Zimbabwe head selector Alistair Campbell said he was saddened by Ervine's withdrawal.
"Zimbabwe Cricket was very excited about Sean coming back into the setup. However, he may not have realised that international cricket is a lot harder than he remembers," Campbell said in a statement.
"He has lived a very comfortable life in county cricket for the last six years and obviously decided at the last minute he might not be up to the challenges of international cricket after all."
The 28-year-old Ervine played five Tests and 42 one-dayers from 2001-04, until he was involved in a players' dispute with national cricket administrators and left the country.
Mawoyo, 25, captained Zimbabwe Under-19s at the 2003 Youth World Cup in Bangladesh and was stripped of the Zimbabwe 'A' captaincy for disciplinary reasons in 2007.
He has been enjoying good first-class form of late and was named as a non-traveling reserve for the World Cup.
Zimbabwe opens against defending champion Australia on February 21 at Ahmedabad and was in Group A beside New Zealand, Pakistan, Sri Lanka, Canada and Kenya.