Fearnley-Whittingstall在網上發布了一個關於他的 "非常親愛的朋友 "的信息，他曾與他的《河畔小屋》電視劇合作。
Writer and broadcaster Nick Fisher, 63, was last seen in Hooke, near Bridport, Dorset on Tuesday afternoon.
Fearnley-Whittingstall posted a plea online for information about his "very dearest friend" with whom he had worked on his River Cottage TV series.
Insp David Parr, of Dorset Police, added: "Nick left the area unexpectedly and has not been in contact with family or friends, which is out of character.
"I would urge anyone who has seen Nick, or a man matching the description given, to please contact Dorset Police."
Fearnley-Whittingstall repeated the police appeal on social media and said Mr Fisher's friends and family were desperate to find him.
"It's so unlike Nick to do this and of course we are very worried for his safety," he said.
Mr Fisher collaborated with the TV presenter and chef as a fishing expert on his River Cottage TV series based in west Dorset, as well as accompanying books.
He is also a BAFTA-winning TV scriptwriter and has written episodes of Eastenders, Casualty and New Tricks.
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