This is the heart-stopping moment a trailer was disconnected from a truck and crashed into an oncoming car in Thailand.

Driver Chanprapha Tongrewm, 59, was travelling along a road in Phetchabun to pick up her mum on August 29 when she approached the pick-up truck dragging a trailer behind it.

But as she passed by in the adjacent lane, the trailer was suddenly detached, veering right into her car and smashing into its bonnet.

Dramatic dashcam footage shows how the breakaway object rolled towards Chanprapha's vehicle, with her screaming in terror as she was unable to avoid the collision.

The crash left the wooden trailer lodged under her sedan's headlights.

A shaken Chanprapha emerged from the accident with a wounded lip, bruised knees, and a sore chest when the airbag deployed. She did not suffer any serious injury.

Meanwhile, the pick-up truck driver, who was not named by officers, agreed to pay for the injured motorist's medical expenses and said he will compensate Chanprapha for the damage to her car.

Thailand has one of the world's worst road safety records. Ministers have set the goal of reducing fatalities from 32.7 deaths per 100,000 people to 12 per 100,000 people by the year 2027.

However, a lack of road safety education in schools along with notoriously easy driving tests, police failures to enforce road laws, and chronic under-investment in infrastructure, all appear to hamper the efforts.