Ministers have been accused of breaking a promise to cut the number of children being “farmed out” to children’s homes huge distances from where they live.
Government reforms in 2012 pledged to cut down “out-of-borough placements” to help combat child sexual exploitation.
Labour MP Ann Coffey will use a Commons debate later to say a “sent-away generation” is in danger of falling prey to paedophiles and drugs gangs.
The government said placements “should meet the needs of children”.
Stockport MP Ms Coffey – chair of the all party parliamentary group for runaway and missing children and adults – said there had been a 64% rise nationally in the number of children being sent to live away between 2012 and 2017.
Figures obtained by Ms Coffey from the Department for Education show the number of children placed in homes out of their borough has risen from 2,250 in 2012 to 3,680 in March 2017.
Ms Coffey said some children are being sent as far as 100 miles from where they live “where they have no friends or family circles or local social workers”, creating a “perfect storm where it is increasingly difficult to protect [them]”.
“Despite the [government] pledge, record numbers of children are being sent away to places where they are more vulnerable to exploitation,” she added.
“These children are running away at a faster rate and are being targeted and preyed upon by paedophiles and criminals who know they are vulnerable.”
The MP said there has also been a huge increase in the number of sent-away children going missing, with the number of incidents more than doubling to almost 10,000 a year.
Children’s charity the NSPCC said going missing from care “puts children at greater risk of physical abuse, grooming and sexual exploitation”.
A Department for Education spokesman said it was updating its strategy to improve responses to missing people and strengthening its care planning and children’s homes regulation to require all homes to have a “clear policy for preventing children from going missing”.
“Local authorities have a statutory duty to make sure that placements meet the needs of children in their care and this includes the location of the placement,” he added.
Ms Coffey was author of Real Voices report – and a subsequent review Real Voices – Are they being heard? – into child sexual exploitation which was commissioned in the wake of the Rochdale grooming case in 2012.
She found almost 650 children reported missing in Greater Manchester in 2014 were at risk of child sexual exploitation or serious harm, with almost half concerning children in care.
Ms Coffey will highlight the links between children going missing and sexual exploitation in the debate in Westminster Hall, which is due to start at 11:00 BST.