The 26-year-old rapper died after suffering a cardiac arrest at his home following a suspected overdose and a number of artists have come forward to remember him.
Diplo tweeted: ''RIP Mac Miller.''
The Chainsmokers wrote: ''Never had the chance to meet Mac Miller but was a huge fan of his music. Our prayers go out to his family and friends. And for those struggling with addiction or know someone who is, please seek help you are not alone these things don't just get better.''
The Knocks tweeted: ''F**kkkkk RIP Mac Miller. That dude had such a bright future and was such a talent. This is f**ked.''
DJ Carnage shared a picture of himself and Mac on Instagram and wrote: ''It's really starting to become normal for me to be woken up to a call that another one of brothers has died..... this shit sucks.....this shit is so wack..... you were one of my biggest supporters... and I was one of your biggest fans... everybody loved you... what you did for rap music will never be forgotten..... thank you for letting me be apart of your legacy.......''
And Rufus Du Sol tweeted: ''Didn't know Mac Miller, but was completely floored by Swimming. Such a beautiful record. Have had it on repeat since hearing it. Such an inspiring piece of art. Very sad day for music. Rest In Peace dude.''
Miller dated Ariana Grande for nearly two years, before they split in May.
The 25-year-old singer - who is now engaged to Pete Davidson - is yet to make a public comment on the news, but is said to be devastated by Miller's death.
A source told 'Entertainment Tonight': ''Although the two ended their relationship, Ariana always shared a deep connection with Mac and wanted nothing but the best for him. Ariana is very upset.''
Another source said: ''Despite their split, Ariana had always been supportive of his sobriety.''
Meanwhile, Miller's family has issued a statement about his death.
It reads: ''Malcolm McCormick, known and adored by fans as Mac Miller, has tragically passed away at the age of 26. He was a bright light in this world for his family, friends and fans. Thank you for your prayers. Please respect our privacy. There are no further details as to the cause of his death at this time.''