This is the shocking moment a baby boy tumbled down the stairs before banging his head on the floor.

The curious 11-month-old infant Rajen Rojanjutharat sneaked up the steps to the bedroom while his mum was distracted preparing food in their home in Bangkok, Thailand, on August 20.

However, the little boy slipped and fell down on his head as shocked parents ran to check on him.

CCCTV footage shows the youngster bouncing on the steps and hitting his head on the floor.

Shocked mum Suchinda said: ‘He was so silent, so I didn't know that he was up to something. I left him playing with his toys.

‘When I heard him cry in pain, I thought my heart would burst out of my chest.'

Suchinda was heard shouting in the background as she rushed to take the boy.

The worried mother with her husband calmed the boy down with his wounded head and took him to the hospital.

Rajen underwent lab tests, and his bleeding wound was stitched up.

However, Suchinda said she was relieved when the doctor confirmed that her boy was fine.

She said: ‘I felt bad for leaving him even for a moment. A lot of things can happen in a minute when you are with a baby.

‘I was relieved when the doctors gave me the lab test results and confirmed my son was okay.'