"The results of the UN Security Council vote on MH17s downing: 11 for (the establishment of a tribunal), three abstained, and only Russia against," the Western-backed leader wrote on his Facebook page.
"The results speak for themselves. But Ukraine will not stop there," he added minutes after the vote.
"The guilty must surely be punished. It is our duty to the victims and their families."
Ukraine accuses Russia of providing pro-Kremlin insurgents with a sophisticated missile that allegedly downed the Malaysia Airlines flight over rebel-held territory last year.
All 298 people on board -- most of them Dutch -- died on the Boeing 777 flight from Amsterdam to Kuala Lumpur.
Kiev believes that the fighters mistook the airliner for a Ukrainian air force jet.
Russia and the eastern separatists reject Kievs account and accuse Ukraines own forces of downing the liner in order to pin the blame on the rebels and discredit their cause.
The final results of a Dutch-led inquiry into the disaster are due to be published in October.
A preliminary international report released last year blamed the downing on a missile but assigned no direct responsibility for the attack.