Experts looked at data on 10,000 children diagnosed under five between 1962 and 2007, and where they lived.
The British Journal of Cancer study is not the first to rule out a link – but previous studies’ methods were challenged.
Cancer Research UK said the results were “heartening” but added monitoring should continue.
Leukaemia is the twelfth most common cancer in the UK, but accounts for a third of all cancers diagnosed in children.
Around 500 new cases were diagnosed in children under the age of 15 in 2010 in the UK.