Almost a quarter (23%) of four to five-year-olds are overweight or obese, data showed today.
The figure rises to one in three (33%) of children in their final year of primary school (aged 10 to 11).
Today's report, from the NHS Information Centre, found there has been barely any change in childhood obesity rates over the last few years.
Of children in the younger reception year, 14% of boys are overweight and another 11% are obese, while 13% of girls are overweight and 9% are obese.
In Year 6, the last year of primary school, 15% of boys and girls are overweight, and 20% of boys are obese alongside 17% of girls.
The data is taken from more than a million children (91% of eligible pupils), as part of the Government's National Child Measurement Programme.
The scheme has been criticised for being voluntary, with research suggesting that some overweight and obese children "opt out" of being weighed and measured, potentially skewing the results.
The report found that children in urban towns and cities were much more likely to be overweight than those living in more rural areas.
Tim Straughan, chief executive of The NHS Information Centre, said: "This is the fifth year of the programme and participation in the study continues to increase with more than a million children taking part.
"The study suggests that weight problems continue to be far worse for older children than for younger children, with one in three Year 6 pupils being either overweight or obese and nearly one in five obese.
"These statistics suggest that more needs to be done at a younger age to combat obesity within primary education and positively encourage healthy eating and participation in physical activity, to reduce future health implications for these children."