This is the heartwarming moment a kind-hearted postman helped an exhausted food vendor push her broken-down trailer.

Yoghurt seller Sunisa Iamsakul, 57, was riding her motorcycle cart to deliver the goods in Krabi, southern Thailand on Wednesday (October 16) when suddenly the engine jammed.

She had to stop on the road side and try to push her cart in the blistering heat to the nearest repair shop.

Fortunately, postman Somporn Butrmud, 30, was passing by. The postie felt for the vendor and helped her.

The postal worker said that he was on his way back from the delivery when he saw the exhausted vendor trying to push her fully-loaded broken trailer.

He said: "I was driving back to the post office when I saw the vendor pushing her broken motorcycle trailer alone.

"She appeared to be so exhausted, so I pulled over and helped her push the jammed trailer to the nearest repair shop."

The vendor said that without his help she might have passed out on the way from heat exhaustion.

She said: "The weather was so hot and I was so tired, it was so surprising that he gave his time to help me and did not ask anything in return."