The handovers appeared to mark a slight easing in tension between the two countries after a sharp escalation late last week, when the rebels -- supported, according to Kiev, by Russian armored columns -- opened a new front in the fighting by capturing the southern coastal town of Novoazovsk.
Ukraine had previously said the men were on a "special mission" and had been detained for crossing the border illegally and supporting a "terrorist organisation", the term it uses to refer to the separatists. Its military spokesman mocked the idea they had "got lost like Little Red Riding Hood in the forest".
Ragozin criticized Ukraine's behavior over the incident.
Read More Ukraine's Poroshenko says close to point of all-out war with Russia
"I consider it unacceptable that our servicemen were detained by the Ukrainian side for so many days," he said.
Ragozin said Russia, by contrast, had promptly returned 'hundreds' of Ukrainian soldiers who at various times have crossed the border when squeezed by rebel forces. He said the latest group of 63 had entered Russia on Wednesday.
"Our lads are upset about everything that happened. They will all receive the necessary psychological and other kinds of help. The lads will all be OK," Ragozin said.
Read MoreEU wields Russia sanctions threat but timing vague
European Union leaders decided at a summit on Saturday to draw up proposals within a week for further sanctions against Russia in the light of mounting evidence of its military involvement in Ukraine, something Moscow continues to deny.