According to figures released by the world body's refugee agency on Thursday, more than 4,800 civilian deaths and injuries were reported over the course of 2018, Al Jazeera reported.
Children accounted for 410 deaths and 542 injuries, the UNHCR said.
Relying on open source data for its findings, the agency noted that nearly half of all the casualties - 48 percent - were reported in the western city of Hudaydah, whose strategic port has been the scene of fierce attacks by Saudi-UAE-backed militants.
The UN figures also showed that a staggering 30 percent of the civilians were either killed or wounded inside their homes, with non-combatants also targeted when traveling on roads, working on farms and at other civilian sites.
"The report illustrates the staggering human cost of the conflict," said Volker Turk, the UNHCR's assistant high commissioner for refugees.
"Civilians in Yemen continue to face serious risks to their safety, well-being and basic rights. Exposed to daily violence, many live under constant fear and suffer in deteriorating conditions, turning in desperation to harmful coping mechanisms in order to survive".