The 'My Generation' legends are the first act to be honoured with the special award at the site of the new monument in Camden Town, London.
Roger Daltrey and Pete Townshend were presented with the honour by Primal Scream's Bobby Gillespie, with fans and friends watching including the likes of Suggs and Jazzie B.
The Who said: "We are honoured to be the first band with a stone on the Music Walk Of Fame.
"Camden has always been vital to London's thriving music scene and is, as we all know, a world-renowned hub for the arts.
"As Londoners, it's very surreal to be immortalised in stone on Camden High Street, and it's quite something to know that people can pop by and see us anytime, albeit virtually!"
The 'founding stone' itself will act at a guide to the unfolding route of the walk, with big names - from artists and creatures to executives and the media - set to be recognised at the global attraction.
Over the course of each year, up to 20 stones will be laid and marked with special celebrations, with AR technology also used to turn the streets into a museum.
The Music Walk of Fame founder Lee Bennett added: "What a great day for music, fans, the world, London, and Camden. To cap it off by having one of the greatest bands of all time, I'm thrilled to bits."
Reflecting on the honour, Roger heaped praise on the British music industry as a whole.
He said: "We're proud of the British music business achievements, and to have it in Camden - London's centre of music, especially in the '60s and '70s - it's just an honour, it's great."
Bandmate Pete added: "We're really pleased to get this - not just because we're the first, if we weren't the first it would've been just as wonderful.
"As Roger said, it's an honour. And I think also what Roger says about British music is true. We still are leading the field in so many areas."