Romania have made an encouraging start to their Euro 2016 qualifying campaign, taking seven points from three matches to sit second behind surprise package Northern Ireland in Group F.
However, a 2-0 victory in Finland on Tuesday has proven to be the final game of Piturca's third spell in charge of the national side.
The 58-year-old was reappointed in June 2011, having guided Romania to the European Championship finals in 2000 and 2008, but will now continue his career in Saudi Arabia.
The Romanian Football Federation (FRF) announced that Piturca's contract had been cancelled by "mutual agreement" on Thursday, with his backroom staff also departing their roles.
Al Ittihad, who have won each of their six games to date this season in the Saudi Arabian Pro League, subsequently confirmed Piturca's arrival on Twitter, and also posted images of their new coach holding a club scarf and signing his contract.
Khalid Al Koroni was sacked as Al Ittihad's coach in August after the club exited the AFC Champions League at the quarter-final stage, with Amr Anwar handed interim control of first-team affairs.
The club were strongly linked with Neil Lennon prior to the former Celtic manager taking over at Bolton Wanderers last weekend.
Romania will hold a press conference on Monday, with FRF president Razvan Burleanu due to address the media.
