Reports the "Hannah Montana" star is with child are false.

MILEY CYRUS is the subject of a new Internet hoax -- one that claims the 14-year-old star is pregnant!

In a fake story that was attributed to popular tween magazine J-14, an unknown prankster altered an item in the magazine and posted the story online.

Now the mag's Editor-in-Chief, JANET GIOVANELLI, is speaking out to ET:

"There are a number of Internet postings pertaining to J-14 that are erroneous. I would like to clear this up. J-14 NEVER reported Miley Cyrus is pregnant. Someone doctored the "This Just In" article that appeared on page 16 of J-14's July 2007 issue. Miley is an intelligent, respectable role model for young girls, and we at J-14 pride ourselves on presenting our readers with credible stories and information. This story is completely fabricated!"