Uggie, the dog who shot to fame in 2011 Oscar-winning film The Artist, has been put to sleep, reports BBC News.
The Jack Russell was put down after suffering from a prostate tumour. The TMZ website put his age at 13, while Reuters reported he was aged 12.
Uggie played Jean Dujardin's dog in The Artist and also appeared with Robert Pattinson in 2011's Water for Elephants.
The terrier "retired" in 2012 but went on to make sporadic TV appearances.
Uggie's owner and trainer Omar Von Muller wrote on Facebook: "We regret to inform to all our friends, family and Uggie's fans that our beloved boy has passed away.
"Uggie had a cancerous tumour in the prostate and is now in a better place not feeling pain."
The dog's most recent credit, according to movie site IMDB, was 2013 TV movie Holiday Road Trip, in which he played a dog called Scoots.
Uggie won the tongue-in-cheek Palm Dog award for best canine actor at the 2011 Cannes Film Festival, and was the first dog to leave his paw prints on cement outside Grauman's Chinese Theatre in Hollywood.