The 17-year-old took to Twitter to comment on the reports, after she posted a very pouty selfie which sparked the allegations.
KIM AND KHLOE KARDASHIAN HAVEN'T SPOKEN FOR SIX WEEKS: 'THEY'RE PROBLEMS AREN'T FIXABLE'
She wrote: "How long are we gonna talk about this lip thing lmao [sic]
"Let's get out lives together guys and talk about some important sh*t. Just talk about something new at least. I'm bored [sic]."
Rumours began earlier this year, when Kylie began uploading pictures showing her with noticeably plumper lips.
KYLIE JENNER SPARKS 'BOOB JOB' RUMOURS WITH REVEALING NEW SELFIE
She put it down to good lipstick, but experts disagree.
One surgeon told Hollywood Life: "That is not just lipstick. Her lips look three times as wide as they did in the 'before' picture.
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"There are permanent fillers and temporary ones. The most popular temporary ones are Juvaderm and Restylane.
"They last about one year. The permanent ones cause significant deformity in the long run."
He insisted: "Usually [lips] get smaller and less plump as you get older, not bigger."
Do you think Kylie has had fillers?