The UN organisation said Israeli bombing in Gaza had killed 68 Palestinians, including 14 children, since November 1.
"The deaths that occurred over the last seven days ... add to a heavy toll the Palestinian children have paid in war since the start of the Intifada in 2000, with 113 children killed until now," Unicef said in a statement.
"That is twice the number in 2005," the NGO added. Unicef underlined that children and teenagers, who make up more than half of the Palestinian population, live in a terrifying state of siege which will inevitably have an enduring impact.
The organisation repeated its position that children's rights must be protected regardless of the environment in which they live.
An Israeli artillery attack in the northern town of Beit Hanun early on Wednesday killed at least 18 Palestinians, 13 of them women and children, drawing world-wide condemnation.

Copyright AFP (Agence France-Presse), 2006