The 72-year-old "Piku" star took to twitter to share the news and welcomed the celebrated actor-writer on the big screen.
"Kadar Khan... Great colleague, writer, contributor to many of my successful films... Returns to film after a long hiatus! Welcome," he wrote.
However, Big B did not mention the name of the film, which will mark Khan's comeback.
Khan wrote the dialogues of many Bachchan starrer film including "Mr Natwarlal", "Khoon Pasina", "Do Aur Do Paanch", "Satte Pe Satta", "Inquilab", "Giraftaar", "Hum" and "Agneepath".