The move puts Google into direct competition with services such as Netflix, Hulu, and Amazon, which have been luring viewers away from cable and broadcast TV.
"Starting Thursday, we're launching a pilot program for a small group of partners that will offer paid channels on YouTube with subscription fees starting at $0.99 per month," a YouTube blog statement said.
The statement said this is part of an effort begun in 2007 "that enables content creators to earn revenue for their creativity."
YouTube released a list of some 50 channels which will be part of the program starting Thursday. Subscription rates go as high as $7.99 per month.
"Every channel has a 14-day free trial, and many offer discounted yearly rates," a YouTube blog post said.
"This is just the beginning. We'll be rolling paid channels out more broadly in the coming weeks as a self-service feature for qualifying partners. And as new channels appear, we'll be making sure you can discover them, just as we've been helping you find and subscribe to all the channels you love across YouTube."
Subscribers will be able to access the channels from a computer, phone, tablet or TV, "and soon you'll be able to subscribe to them from more devices," the statement said."
Google bought YouTube in 2006 for $1.65 billion. The service is believed to generate a small amount of revenue from advertising, but the content has been free up to now.
YouTube has gradually added professional content, such as full-length television shows and movies to its vast trove of amateur video offerings in a bid to attract advertisers.
The new paid channels include Acorn TV, which offers ad-free British TV programs at $4.99 per month; National Geographic Kids, at $2.99 a month or $30 a year; and PrimeZone Sports, at $2.99 per month.
Other channels offer programming from UFC (Ultimate Fighting Championship), Comedy.tv, and iAmplify Fitness. A children's channel from Sesame Street is also coming, YouTube said.
Absent from the list are the big media-entertainment firms such as Comcast and Time Warner, which offer their programs through services like Hulu or Netflix or their own subscription websites.
But YouTube said it had "more than one million channels generating revenue on YouTube," and added that "one of the most frequent requests we hear from these creators behind them is for more flexibility in monetizing and distributing content."
Earlier this year Google said more than a billion people use YouTube each month, with viewing on smartphones helping drive growth.
YouTube confirmed early this year that its evolution as an Internet stage for video may include subscriptions to content that creators expect people would pay to watch.
The video service has been gaining prominence in other areas, such as a launchpad for new musicians, and a forum for political discussion.