The 73-year-old was named Best Actor for his role in the Shoojit Sircar directorial at the 63rd National Film Awards which were announced on Monday.
“To them that congratulate me for the National Award – most grateful… Thank you is never enough expression,” Amitabh posted on Twitter.
He has won the honour for “Agneepath”, “Black” and “Paa” in the past.
The actor celebrated the win with wife Jaya Bachchan and the crew members of an advertisement he was shooting with the latter.
“Working with the wife today for an ad, promotion and some moments from there… They celebrate my National Award on set and then as I leave the studio they burst a few crackers… Sweet,” he posted on his blog alongside some images from the set.
The “Wazir” actor also congratulated other winners including Gujarat, which was named the most film friendly state at the National Film Awards for its efforts to ease shooting of films.
“Congratulations National Award winners and to the State of Gujarat that wins ‘Most Film Friendly State’,” he posted.
The actor is currently the brand ambassador of Gujarat Tourism.