Eight of the injured soldiers suffered concussion during artillery shelling over the weekend near Luganske, a village 50 kilometres northeast of the rebels' de facto capital Donetsk, according to military spokesman Andriy Lysenko.
Despite the agreement of a ceasefire aimed at halting the 26-month war in east Ukraine, shelling flares up frequently and Kiev has lost several soldiers in recent weeks.
The rebel defence ministry in the self-proclaimed Donetsk People's Republic on Sunday accused Ukrainian forced of shelling Gorlivka and Donetsk, injuring four civilians - two women and two men.
Kiev and the West have accused Russia of supporting rebels and deploying troops across the border, both claims that Moscow denies.
Ukraine's pro-Western President Petro Poroshenko attended a summit of NATO leaders in Warsaw that ended Saturday with the alliance agreeing to bolster its eastern flank after Moscow's annexation of Crimea and the Ukraine conflict.