Statistics released last week by the charity End Child Poverty show nine percent of children in the borough - 2,631 - were living with hardship last year.
Nationally, the borough is one of 89 constituencies that has met Government targets to reduce child poverty rates to 10 per cent or below.
But Una Loughrey, of the Link Foundation which helps disadvantaged children in East Berkshire, said the campaign's findings are 'shocking'.
"It's terrible to think there are so many children living in conditions they shouldn't have to, especially in such an affluent area'.
The data comes from the number of families without work or on very low incomes based on claims for tax credits.
Some of the borough's most deprived wards include Oldfield, Furze Platt, Datchet, and Clewer North and South which each have between 170 and 270 children in poverty.
But only four youngsters are thought to be facing adversity in Eton and Castle.
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