19 August 2015 Last updated at 08:34 BST
It's after Newsround raised a complaint, in November 2014, with the Advertising Standards Authority which makes the rules for adverts in the UK.
Newsround highlighted a group of UK vloggers who were paid to say good things about Oreo biscuits, but none of the videos were labelled as adverts.
Now if a vlogger is being paid to say something good about a particular product or service then they must clearly say that it's an advert.
New guidelines have come out telling vloggers that they need to be clear and honest with their followers if they're being paid to say something is good.