The alarm was raised at approximately 9.45 am by postman Chris Williams, of Saundersfoot, who saw smoke billowing out from one of the vents when he went to deliver the post.
"I looked through the window, could see the smoke," said Chris. "I stepped back and 'phoned the fire brigade and with that the caravan was ablaze."
Firefighters from the town were quickly on scene and two of them, wearing breathing apparatus sets, used hose reel jets to extinguish the fire. No-one was injured in the fire.
Our picture of the drama unfolding was captured on camera by town councillor Trevor Hallett.