The singer was heavily criticised for her performances of 'Video Games' and 'Blue Jeans' on the show, which was guest hosted by the Harry Potter actor on Saturday (January 14).
Speaking at the BAFTA nominations announcement, Radcliffe is quoted by BBC Newsbeat as saying: "It was unfortunate that people seemed to turn on her so quickly.
"I also think people are making it about things other than the performance. If you read what people are saying about her online, it's all about her past and her family and stuff that's nobody else's business."
He added: "I don't think it warranted anywhere near that reaction."
Following her performance on the comedy show, Del Rey also received criticism from Juliette Lewis on Twitter who compared her to "a 12-year-old in their bedroom when they're pretending to sing and perform".
Lewis later deleted her tweet and insisted that Del Rey has "great haunting melodies" and described her as a "fresh and yummy songwriter".
Lana Del Rey's debut album Born To Die will be released in the UK on January 30 and in the US on January 31.
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Watch Lana Del Rey's performance of 'Video Games' on Saturday Night Live below: