The trial, which starts in December, will also allow users to post video clips from their mobiles more easily.
It is likely that similar arrangements will happen in future with mobile operators looking for a slice of what's on offer with the social-networking services.
The new deal means that VCast subscribers, who pay $15 a month to watch and download video to their mobile, will now have access to a limited number of approved videos from YouTube as well.
Posting content from mobile handsets to YouTube has previously needed an email address but subscribers to Verizon's wireless media service Vcast will be able to upload content using a five-digit short code.
The deal with Verizon is part of a limited trial for the popular site on the small screen and more than 100 million video clips are viewed every day on the YouTube website.
