Some 580,000 Ukrainian children have been deeply impacted by the crisis in the country with some 200,000 requiring psychosocial support, UNICEF said Friday.
The UN agency said that children have been strongly affected by the conflict involving pro-Russian separatists in the eastern part of Ukraine in areas that are not under government control or are close to the front line.
"Two years of violence, shelling and fear have left an indelible mark on thousands of children in eastern Ukraine," said Giovanna Barberis, UNICEF representative in Ukraine.
"As the conflict continues, we need to reach these children urgently to meet their physical as well as psychological needs."
UNICEF found that more than 200,000 children have been displaced and at least one in five schools in the conflict zone have been damaged.
Because of destroyed infrastructure and a disrupted healthcare system, Ukraine is facing a polio outbreak.
UNICEF called for unhindered humanitarian access in Ukraine to reach children, who are now suffering through the cold winter.