He will replace Dame Alison Nimmo, who is due to step down at the end of the year from her role as chief executive, where she ran the Royal Family’s £14bn portfolio.
The Crown Estate’s holdings include property in London’s Regent Street and a fast-growing offshore wind turbine business.
Labbad’s appointment requires a Royal Warrant and was signed off last week.
Australian-born Labbad began his career 22 years ago working for the property and construction developer.
Since August 2014, he has held the dual roles of chief executive officer, International Operations & Europe, responsible for overseeing the expansion of Lendlease’s Europe, Americas and Asia regions.
He will remain with Lendlease for six months to allow the board time to find his replacement and ensure a smooth transition for his successor.
Under Labbad’s control, Lendlease has steadily expanded in the UK, taking forward in London the Stratford International Quarter and Elephant & Castle regeneration as well as securing the master developer deal for the Euston over-station redevelopment.
More recently housing charity Peabody picked Lendlease as preferred bidder for the £8bn, 11,500 home, Thamesmead Waterfront development in south-east London.
Also Lendlease has made inroads in Birmingham securing the contract to deliver the £350m Commonwealth Games village and £1.5bn transformation of the 17ha Smithfield city centre site in partnership with the council.