"Has #MeghanMarkle said anything about the death of George Floyd, her fellow POC? Exactly what has she ever done for black people? Certainly nowhere near what they have done for her. Her biggest interest is herself," one wrote.
"Wondering why #MeghanMarkle and #PrinceHarry are quiet about the racism occurring in the US? #silenceiscompliance," another stated.
One fan even wrote: "So where is Meghan now. Black Americans stood by her and #PrinceHarry We're so proud of her. SPEAK UP SIS! WYA."
A resurfaced clip of Duchess Meghan from 2012 emerged this week from the time she filmed a segment on racism for non-profit organisation Erase the Hate.
In the video, the former Suits star recounted experiences of experiencing racial slurs and insults, and her hopes for the future.
"I hope that by the time I have children that people are even more open-minded to how things are changing," the now mum-of-one said at the time.
"I am really proud of my heritage on both sides, I'm really proud of where I've come from and where I'm going."
When Harry and Meghan first started dating, Prince Harry also spoke out against racism and sexism in a rare statement.
The red-headed royal highlighted that his then-girlfriend had been subject to "a wave of abuse and harassment".
"Some of this has been very public - the smear on the front page of a national newspaper; the racial undertones of comment pieces; and the outright sexism and racism of social media trolls and web article comments," the statement read.