Fans will flock to the West Kowloon Waterfront Promenade from Friday to next Sunday to see some favourite musicians, and hopefully discover new favourites.
The overseas bands this year will include Irish alternative rock band Two Door Cinema Club, Scottish indie rockers Franz Ferdinand, and the Canadian electro-pop group Metric.
"We don't know what were going to play [yet]," Metric's James Shaw told Young Post, "but I'm sure it will be a high-energy, fancy, good time. We've never been to Hong Kong and are very excited."
Clockenflap headliners: Scotland's Franz Ferdinand and Hong Kong's G.E.M. (below)
They will be joined by many smaller acts from all over the world - such as Australia's Cloud Control and Canadian twins and festival favourites, Tegan and Sara - jamming to their own styles.
This is the first time the festival has called upon local talent to headline the party. One of the top acts is local singer Gloria Tang Tsz-kei, better known as G.E.M., who is known for her alternative rock style.
G.E.M., who will play a six-song set, says the festival will provide Hong Kong fans with music they're familiar with, but also give them a chance to learn how to loosen up.
"Shows like these can make the Hong Kong crowd more engaging. Local fans are sometimes, well ... Let's say you play something more mid-tempo or groovy. They're too rigid, and they don't know how to react," G.E.M. says.
"It often takes a hard rock gig for them to eventually feel comfortable waving their glow sticks in the air.
She once attended a music festival in Britain when on a study tour there, and saw what a festival starring international mega-stars such as Justin Timberlake and will.i.am could do for people's musical experience.
"If Hong Kong can become like [other major international cities] and host more music festivals, festival-goers can influence others," she says, hoping this will open people to new genres.
Another local headliner Ellen Joyce Loo, half of former indie duo at17, thinks of Clockenflap as a melting pot for musicians to interact and learn from one another.
"There are a couple of new indie bands from Hong Kong that are going to be playing there, such as Little Red Riding hood and TFVSJS, so I [think I will] actually watch those performances, too," says Loo, who is determined to play upbeat and thumping rock.
Loo likens Clockenflap to similar festivals she has attended in Shanghai and Beijing. "I would watch other bands perform before and after my own performances.
"Once I went to watch a band and had to delay my own performance," she jokes, hinting that if this year's bands are as good, she'll be doing that again at this year's Clockenflap.
So if you see Loo rushing onto the stage on the day she performs, don't blame her.
Also rocking at Clockenflap will be bands from the mainland - such as world-touring band Hanggai, which plays high-intensity Mongolian punk rock, and Cui Jian, the 52-year-old "father of Chinese rock".
"I always ask myself why there weren't any music festivals similar to other festivals overseas in Hong Kong," Loo says. "Now we finally have one that has a really good reputation, where all the bands are fighting to get time on stage."
(Additional reporting by Leon Lee)