Gordon Henderson, MP for Sittingbourne and Sheppey, received 30% burns to his body and spent 10 days in intensive care after the accident on 26 July.
"I can remember vividly. It really was terrifying," said the Conservative MP.
"I hope it teaches everybody else a very valuable lesson. Do not ever use petrol on a bonfire."
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Mr Henderson said he had recently built a brick container for bonfires in his garden at Eastchurch, Kent.
"I built the bonfire and I put the petrol on it but I hadn't taken into account the build-up of fumes," he said.
"When it went up it was like a bomb exploding in my face because there was a three-sided container and all the force came to me.
"My hair caught light but with the rest of me it was the heat that caused the burns."
Mr Henderson's wife Louise cooled him down with a garden hose and took him Sheppey Community Hospital.
An air ambulance was then called to fly him to Tunbridge Wells Hospital, from where he was taken to the Queen Victoria Hospital in East Grinstead.
"I realised then that if they were taking me to East Grinstead, which is a fantastic burns hospital, that it was something really serious," he said.
Kent Fire and Rescue Service said it urged people not to use petrol to light bonfires or barbecues.
"Use firelighters or rolled-up newspaper and wood but please don't put flammable liquids on bonfires," said community safety spokesman Charlie Smith.
"The burns that can result from these fires can be really nasty and they can take a long time to heal."
An MP has said he is still suffering flashbacks after a bonfire he doused with petrol to set it alight exploded in his face.