There was a terrifying moment passengers realised their plane door was open at 10,000ft.
The plane took off without the door being properly sealed and a visible gap could be seen between the doors.
Some people on board said they suffered headaches and felt pain in their ears.
The plane was forced to return to Chebu Airport in Seoul where 163 passengers were offloaded.
Video filmed inside the aircraft showed a gap between the door and the door frame making a strange noise.
Seoul's Yonhap news agency said the Jin Air flight bound for South Korea's south-eastern port city of Busan returned to Cebu after about 30 minutes in the air.
Passenger Kim Jin-bae said: "The flight turned back about 30 minutes after (takeoff) because the door was open and the gap was big enough to put a finger in it."
Kim added: "I thought I would die here because I was numb with a headache."
Another passenger called Lee Sang-gyu said: "Adults felt so much pain because of (the pressure on) eardrum. How painful could it be for children?"
The passengers finally arrived at Gimhae airport in Busan on another plane at 9pm - 15 hours later than scheduled.
Last month, terrifying footage of a plane crash filmed on a GoPro surfaced when a small plane crashed into a field.
