The Austrian film-maker was also named best director, while the film's star Emmanuelle Riva won best actress.
The French-language drama tells the story of an elderly couple dealing with the aftermath of a devastating stroke. It previously won Cannes' Palme D'Or.
Daniel Day-Lewis was named best actor by the panel of 60 critics.
He received his award for playing America's 16th president in in Steven Spielberg's historical drama Lincoln.
The movie, which will be released in the UK on 20 January,  also won best screenplay.
Amy Adams was chosen for the best supporting actress accolade, for her role in The Master, while Matthew McConaughey received best supporting actor for his films Magic Mike and Bernie.
The National Society of Film Critics includes some of the most prominent movie writers in the US, including Roger Ebert of the Chicago Sun-Times and Kenneth Turan of the LA Times.
They gathered at the Lincoln Center in New York to choose their winners, with the evening dedicated to the memory of Village Voice critic Andrew Sarris, a founding member of the society, who died last year.
Elsewhere, the Houston film critics' society named Ben Affleck's political thriller Argo its favourite film of the year. Jennifer Lawrence picked up best actress for comedy-drama Silver Linings Playbook while Day-Lewis again won best actor for Lincoln.
Critics' awards are seen as key steps towards the Oscars.
Members of the Academy of Motion Picture Arts and Sciences had until Friday night to cast their ballots, with the nominations announced this Thursday, 10 January.
Michael Haneke's heartbreaking drama Amour has been voted the best picture of 2012 by the US National Society of Film Critics.