In a video available online since Sunday, the 27-year-old Swede whose real name is Felix Kjellberg, can be heard using the N-word in an expletive-laden tirade during a video game trial.
PewDiePie is known for posting humorous clips and testing video games for more than 57 million followers on YouTube, making him the site's most watched blogger.
One game developer said he was going to file a complaint to prevent the Swede from playing his games online.
"He's worse than a closeted racist: he's a propagator of despicable garbage that does real damage to the culture around this industry," developer Sean Vanaman tweeted.
Swedish Youtube star Felix Arvid Ulf Kjellberg also known as PewDiePie poses on the red carpet at the Inaugural Social Star Awards in Singapore, 23 May 2013. Source: AAP
On Twitter, some users recalled that PewDiePie has "already been a racist memelord."
Kjellberg, who has yet to comment on the affair, in February lost contracts with YouTube and Disney after he posted several videos containing anti-Semitic and Nazi remarks.
And in September 2016, he was temporarily blocked on Twitter after making a joke about the Islamic State group.
PewDiePie, real name Felix Kjellberg, the most-subscribed YouTuber in the world during a photo call to launch his book 'This Book Loves You'. Source: AAP
