Close to 300 children aged 11 or under were taken to A&E last year after drinking too much alcohol.
A BBC Radio 5 Live investigation found that a total of 6,500 under-18s were admitted to A&Es in 2012/13.
Five years of data was revealed through freedom of information (FOI) requests with 189 NHS organisations.
During 2012/13 there were 293 cases of children aged 11 or under attending A&E with alcohol-related conditions - a third more than in 2011/12 when there were 216 cases.
And girls were more likely to be admitted to A&E than boys, a reversal of past trends, according to the BBC.
Professor Sir Ian Gilmore, chairman of the UK Alcohol Health Alliance said: "I think in under-11s, it's mainly experimenting, but I think we see children in the 11 to 16-year-old range who are beginning to drink regularly."
He added: "There are some encouraging signs in that the numbers of under-18s drinking is probably falling, but those that are drinking are probably drinking earlier and drinking more heavily, so we certainly can't be complacent."
Elaine Hindal, chief executive of Drinkaware, told the BBC that the incidence of drunkenness among under-11s was "really alarming".
She said: “Parents need to simply be aware of the dangers of drinking, particularly with younger children. Their bodies can't take it, they're more at risk of alcoholic poisoning, they are more likely to be a victim of alcohol-related violence."
Public Health England states that one in four underage drinkers consumes more than 15 units a week - the equivalent of seven pints of lager.
The official advice from the chief medical officers across the UK is that no children should be given alcohol until they are 16, and alcohol should only be given to older teenagers under supervision of a carer or parent, and never on more than one day a week.
A Department of Health England spokesman said: "We know that fewer young people are drinking and being admitted to hospital as a result.
"But with more than one million alcohol-related hospital admissions overall in the last year we know too many people are drinking too much and that alcohol places a heavy burden on the NHS, costing around £3.5bn every year. "