Sahir, whose song "Me and Layla" is one of the most popular in Middle East music, was introduced by the United Nations Children's Fund at a news conference inside Baghdad's heavily fortified Green Zone on his first trip back to his homeland in 14 years.
"I hope I can deliver a message ... I know the children (here) have suffered deprivation for many years," Sahir said.
Sahir, born in 1957 in the northern city of Mosul, started his career in the 1980s and gained a reputation for performing poems by prominent Arab poets.
UNICEF said he would focus on raising awareness and mobilizing support to respond to the needs of the most deprived and vulnerable of Iraq's 15 million children.
"It is the right of the people to work, have a good life, and have a happy childhood," Sahir said.
Iraq is trying to rebuild after decades of dictatorship, war and international sanctions.