Farah, who returned to the side for the first time since 2009, played in all three matches as the Blues went down valiantly 2-1 following a last-ditch Cooper Cronk field-goal in game three at Suncorp Stadium.
The award caps off a remarkable Origin campaign for the 28-year-old, who only came into the team after Newcastle veteran Danny Buderus was ruled out of game one with an Achilles tendon injury.
Farah was one of NSW's best performers in the opener in Brisbane and made a herculean 63 tackles in the 16-12 win in game two at ANZ Stadium in June.
The Wests Tigers skipper beat off competition from Josh Morris, last year's winner Paul Gallen, Brett Stewart and Greg Bird for the award.
Other former recipients include Jarryd Hayne, Matt King and Steve Menzies.
Penrith's Shane Shackleton won the NSW Cup player of the year award following a strong season for Wentworthville Magpies.
The former City Origin representative was on the outer at Parramatta for most of the season under former coach Stephen Kearney, before moving to the Panthers late in the year.
