More than a quarter of children in two Braintree neighbourhoods are living below the breadline.
Figures from the End Child Poverty Campaign show Braintree East and Bocking South have the highest child poverty levels in the district.
One in four children in Witham West and Witham North were also found to be living in poverty.
Researchers classed poor families as those receiving unemployment benefit or working tax credits, where their income was less than 60 per cent of the average.
It is also based on local unemployment figures.