The impoverished Arab country descended into conflict in 2014, leading to what has been described as the worst humanitarian crisis in the world.
Also on Friday, the latest airstrikes by the Saudi-led coalition hit a house in the south-western province of Taiz, killing at least seven people from one family.
According to DW, the report by UN Secretary-General Antonio Guterres documented thousands of grave violations against children between April 2013 and December 2018.
"The suffering of children in Yemen has worsened during the reporting period, becoming simply appalling," Virginia Gamba, the UN special representative for children in conflict, said. "The civilian population, especially children, is kept hostage of a conflict they didn't choose to be in."
The report said the worst statistic in the list of violations was the 7,508 children who were killed or maimed by airstrikes, shelling, ground fighting, mines or suicide attacks.
The second largest violation was the use of child soldiers, with 3,034 children verified as recruited — 1,940 of them by the Houthis and 274 by Hadi government forces.
Attacks on schools and hospitals remained alarmingly high, the report said, with buildings severely damaged or destroyed in 345 out of the 381 cases.
It also documented 11 incidents of rape and sexual violence, but stressed that cases were under-reported "mainly for fear of stigmatization and lack of appropriate response services."
On the other hand, the United Arab Emirates, a key member of the Saudi-led coalition fighting in Yemen, is scaling back its military presence there as worsening U.S.-Iran tensions threaten security closer to home, four western diplomatic sources said.
It has pulled some troops from the southern port of Aden and the western coast, two of the diplomats said, areas where the Gulf state has built up and armed local forces who are leading the battle against the Iran-aligned Houthi group along the Red Sea coast.
Three of the diplomats said Abu Dhabi preferred to have its forces and equipment on hand should tension between the United States and Iran escalate further after attacks on oil tankers in the Gulf and Tehran's downing of a US unmanned drone.