"Four-hundred-seventy-eight civilians have died, including 30 women and seven children," Deputy Health Minister Vasily Lazorishinets said in a press conference.
The figure is more than double the number of Ukrainian military casualties on the battlefield since fighting broke out in April with the separatist rebels in the east, which Lazorishinets put at 173.
He added that 1,392 civilians, including 104 women and 14 children, and 446 troops had been injured in the same period.
No figures of casualties have been released on the rebel side, as most of their dead were buried in a hurry on the spot, especially those fallen after government troops retook the city of Sloviansk last week, or were sent back to Russia, their country of origin, according to pro-Russian separatist sources.
Kiev last April launched an anti-terrorist operation
The rebels announced on Thursday that they had killed 22 Ukrainian troopers overnight near the towns of Sloviansk and Kramatorsk, which were re-taken a week ago by Ukrainian forces.
Kiev last April launched an anti-terrorist operation to recover the eastern regions of Lugansk and Donetsk, under control of the separatists.
The Ukrainian National Security and Defence Council has said that Kiev was planning to besiege the cities of Donetsk and Lugansk to "force the separatists and criminals to disarm".
Stanislav Rechinski, a spokesman for Ukraine's interior ministry, said Wednesday night that the two cities, which together have 1.4 million inhabitants, could be in the hands of government forces within a month.
Meanwhile, Russian authorities declared a state of emergency Thursday in six southern regions of the country, due to the number of refugees arriving from neighbouring Ukraine.