Blake, a 25-1 outsider to win, is a Goldsmiths College music graduate who was previously nominated for the Mercury for his self-titled debut album which he recorded at his home in New Cross, south east London.
Accepting his award, he said it was "amazing" to be in the running for an award with chart veteran David Bowie.
Asked what he would spend the money on, he said: "I'll make sure it goes to some good use".
He added: "This is the first award I've ever won apart from a tennis trophy which I won when I was about 12-years-old at my school and I'll hold them in equal esteem".
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Marcus Willis, a current club coach ranked 772 in the world, came through six qualification matches to reach this year's tournament.
Mouth artist Henry Fraser has posted a video showing his works from the first 18 months of painting and drawing.
The ex girlfriend of Ben Butler, who was jailed for murdering his daughter Ellie, has spoken of the abuse she suffered with him.