The organization said it was frustrated by a decision Sunday to keep Andrei Yurov, a member of a Russian presidential council on human rights, out of Ukraine.
"Instead of driving out human rights defenders, the Ukrainian government should be open to scrutiny of its human rights record during this crisis," Rachel Denber, the group's deputy European researcher, said Monday in a statement from Berlin.
Human Rights Watch said Yurov was supposed to meet with Council of Europe Human Rights Commissioner Nils Muiznieks in Kiev to discuss the response by Ukrainian authorities to ongoing protests.
Russia's state news agency RIA Novosti reported the advocate was barred from entering the country Sunday.
Muiznieks, in a statement issued Monday, said hundreds of people were injured and several were killed between November and January.
"Excessive force was used against protesters by law enforcement officers and others working with them in recent months in Ukraine," he said. "It is important to prevent any further violence and to ensure accountability for the serious human rights violations which have already occurred."
Protests erupted in Ukraine, a former Soviet republic, when the government suspended efforts to sign free trade and association agreements with the European Union. The Ukrainian government said the decision was made to protect economic ties with Russia.