Another 10,100 people are still missing in the devastated city, the UN's Office for the Coordination of Humanitarian Affairs said, using Red Crescent figures, AFP reported.
Elsewhere in eastern Libya outside Derna, the flooding took an additional 170 lives, the update said.
“These figures are expected to rise as search-and-rescue crews work tirelessly to find survivors,“ the UN update said.
Nearly a week after Storm Daniel hit northeastern Libya, “the humanitarian situation remains particularly grim in Derna, “the update said.
Severe drinking water problems have gripped the city, and at least 55 children were poisoned from drinking polluted water, it said.
In surrounding areas, most of which have seen years of armed conflict, the UN warned of the dangers of landmines shifting from floodwaters, threatening civilians who enter on foot.