The alleged sexual assault dates back to the 1980s and is said to have taken place in London.
Merseyside police first received the report on Wednesday morning, before referring the case to Scotland Yard.
The allegation will now be assessed by officers from Child Abuse and Sexual Offences Command.
The UK investigation comes after the New York police re-opened a 2004 case against the 65-year-old.
An allegation was made by former aspiring actress Lucia Evans, published in the New Yorker, that Weinstein forced her to perform a sex act on him in his Miramax offices in 2004.
NYPD detectives are also reviewing public allegations against Weinstein to identify, locate and interview any possible victims or witnesses.
Sky News US Correspondent Hannah Thomas-Peter said: “There may well be investigations of a similar nature going on in Los Angeles and possibly in Utah as well because there were some allegations about what happened at a Sundance Festival some years ago.
“It’s slightly complicated because some allegations may well have expired under the statute of limitations, but police need to rule all of that out, to make sure that they’re not missing the chance to go after a potential crime on their patch.”
A flood of sexual harassment, assault and rape claims have surfaced against the producer since The New York Times published a report alleging a history of abusive behaviour dating back decades.
A police recording was also published in the New Yorker in which Weinstein appeared to admit to groping Italian model Ambra Battilana Gutierrez.
While prosecutors said they were “sickened” by the recording, they claimed there was not enough evidence to secure a conviction.
British actress Kate Beckinsale is the latest woman to speak against Weinstein, calling him “an emblem of a system that is sick.”
Gwyneth Paltrow, Angelina Jolie, Lea Seydoux and Cara Delevingne are among a growing chorus of high-profile women who have accused the producer of sexual harassment or assault.
Jane Fonda said she should have spoken out against Weinstein last year when another actress – who has since gone public – told her about sexual harassment allegations against him.
The Hollywood producer has previously denied any allegations of non-consensual sex.
When approached outside his daughter’s home in Los Angeles Weinstein told photographers: “I’m not doing okay, I’m trying – gotta get help. You know what? We all make mistakes.”
He is now understood to be undergoing rehabilitation for sex addiction in Arizona.
Following the scandal, the producer has been fired from his own company and left by his wife, British designer Georgina Chapman.
Bafta – the British Academy of Film and Television Arts – has suspended his membership, while the Academy of Motion Picture Arts and Sciences – which hosts the Oscars – will hold a meeting on Saturday to discuss whether to suspend him.