The disgraced Hollywood producer was spending some time with his sober coach at an Arizona restaurant in the Sanctuary Camelback Mountain Resort grounds Tuesday when another patron identified only as "Steve" approached him along with a friend who had been filming the two.
The restaurant manager tells TMZ Weinstein, who is in the state seeking treatment following accusations of rape and sexual misconduct, politely declined the request and shook the fan's hand.
The maker wasn't hurt and purportedly declined to call police, as per nearby ABC subsidiary KNXV-TV.
Steve, who tells TMZ he had been drinking, told the movie boss he was "a piece of s**t for what you did to these women", and then threw a punch at him.
There is no word on whether or not Weinstein filed a police report.
Weinstein has been living in Arizona at a rehab facility following accusations from almost 100 women that he sexually harassed/assaulted them.
Steve said to the website he "had quite a bit to drink" and asked his friend to record a video of Steve confronting Weinstein. Among the accusers were actresses Ashley Judd, Salma Hayek, Lupita Nyong'o and Gwyneth Paltrow.
Weinstein has vehemently denied all allegations of non-consensual sex.