An Australian couple was terrified when an out-of-control fishing boat rammed a ferry full of tourists traveling from a Thai island.

Tom Holzer and his wife Andi were onboard the vessel off the coast of Koh Chang when the trawler appeared on the starboard side on Monday afternoon.

Holidaymakers braced themselves as the wooden boat came steaming towards them, seemingly with little effort to slow down or steer course.

The couple captured the moment the fishing ship crashed into the side. Miraculously, both ships were unscathed and continued the journey without sinking.

Shaken passengers believe the captain of the boat could have fallen asleep or been drunk and not noticed where he was sailing.

Following the crash, three members of the crew emerged and were seen scrambling onto the deck.

Tom said: 'I still can't get over it. There were many people on the ferry.

'The captain might have fallen asleep and put the shift on automatic mode. Everybody was shaken afterwards. Thankfully the fishing boat was small and did not cause more serious damage.'