Sichuan train track
The then 8-year-old boy ended up in Sichuan province after accidentally boarding train (representational image)Dennis/Flickr

A man in China has been reunited with his mother after going missing almost 30 years ago.

The man, who has not been named, wandered onto a train at a station in his home in Ziyang county, Shaanxi province in 1986, aged just 8-years-old.

After he climbed onto one of the carriages, the train moved off and several hours later, he arrived in Sichuan province, completely alone, more than 200km from his home.

He wandered around for four days before a family in Qu County found him and took him in. They adopted him and gave him a new name.

Twenty-nine years on, the man could remember very few details of his life before he got lost – just the names of his home county, his uncle and mother.

On Mother's Day, he left a message on the Ziyang County Public Security Bureau website explaining how and when he got lost. According to the Huashang Daily, the message said he missed his mother and hoped the police would be able to help find her.

Authorities replied immediately and began work searching for the women. Within just 10 days, police had managed to track her down and a meeting was arranged for the estranged pair.

They showed her a photo of the man as an adult and she reportedly recognised him instantly.

His mother, now 63, told reporters at the reunion: "I thought I'd never see my child in this life again."

The man said he had considered looking for his mother before, but worried about upsetting his adoptive parents.

However, he realised he might never get the chance to see her again as she got older: "They will understand my feelings. They are my family," he said.