Over the weekend someone on Reddit compared the hit with a 2016 track by Jase Harley - sparking a big debate.

The rapper in question has since posted on Instagram saying he too thinks his track was Childish Gambino's inspiration.

But a screen grab of a now-deleted tweet by Gambino's manager seems to show him denying plagiarism.

The video for This is America deals with police brutality and gun violence

This is America was released earlier this year and has since made the top 10 in the UK and number one in the US, while the video has been watched 300m times on YouTube alone.

It talks about black oppression, police brutality and gun violence in America.

But fans have been arguing online about whether it's too similar to another track, which was released in 2016.

The rapper in question - Jase Harley - says he, too, thinks there are similarities.

"I feel extremely humbled to be recognised and labelled as one of, or the original inspiration, for one of the most important pieces of music and visual art of our time," he posted on Instagram.

"I appreciate all the love and support! But please don't let this controversy dilute the message me and Childish Gambino are trying to convey."

He also implies that he has no interest in taking legal action - and that he'd be happy with a "shout out".

You can read his full statement below.

Childish Gambino's manager, Fam Rothstein, also looks like he's got involved.

In a tweet that's since been deleted, but that was screen-grabbed by websites including ABC, he appears to claim that This is America is older than American Pharaoh.

"The internet is a place of no consequences," the tweet says. "This song is three years old and we have Pro Tools [music editing software] files to prove it."

Another deleted tweet posted from his account a few minutes later appears to say his words should be taken as an official "comment from the label".

Newsbeat has contacted representatives for Childish Gambino for comment.