"As Myanmar continues to undergo wide-ranging reforms, it is important to assess the current human rights situation and to reflect on positive developments and remaining challenges," he said in a statement.
Quintana said he was particularly concerned about fighting in northern Kachin state, where rebels vying for autonomy have clashed with Myanmar forces.
"I will be lending my voice to calls for a cease-fire and progress in addressing minority issues," he said in a statement.
Quintana arrives Monday in Myanmar for a five-day visit.
World leaders have pressed for an easing of sanctions against Myanmar in response to political reforms that began with general elections in 2010. The status of political prisoners, censorship and simmering conflict in the country known formerly as Burma have sparked renewed concerns, however.
Human Rights Watch stated last week that political reforms by the government in Myanmar have been oversold by members of the international community.