UNICEF is warning that despite the spiralling numbers the organisation may have to consider cutting some vital services because of a lack of funding.
Some 6.6 million children now need help in the region, the agency says, a figure that has gone up by a third, or about two million, since June 2013.
"That's an astonishing number and it's one that is rising very, very fast," UNICEF spokesman Simon Ingram told reporters in Geneva.
"There is actually a very real risk that as a result of this funding crisis and unless the money does come in we will be forced to discontinue some of the critical services that we are providing," Ingram said.
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UNICEF is especially worried -- given the hot start to the summer in the region -- that it may soon have to halt water and sanitation services in Iraq, Lebanon and Jordan, which along with Turkey are hosting the lions share of the Syrian refugees in the region.
Of particular concern is polio, with thirty-six cases of the crippling and potentially fatal disease discovered in Syria this year. Two cases have been detected in Iraq, according to the UN.
Since the Syria conflict erupted in March 2011 more than 162,000 people have been killed and millions displaced.
In all, 10.9 million Syrians -- nearly half of the population of 22 million -- are in desperate need of humanitarian aid inside the country, according to UN figures. A full 5.1 million of them are children.
With the conflict showing no sign of abating, the UN expects the number of refugees in the region to rise to 3.6 million by the end of the year.
Also today, the UN's refugee chief Antonio Guterres presented a revised plan for addressing the wider Syrian crisis, urging donors to cough up the rest of the USD 3.74 billion (2.75 billion euros) needed this year to help Syrian refugees across Lebanon, Jordan, Turkey, Iraq and Egypt.