Quintana met South Korean Vice-Unification Minister Suh Ho and said he discussed humanitarian aid for N Korea with the Minister, Efe news reported.
Around 10 million North Koreans around 40 per cent of the population are facing food shortage this summer due to drought and crop failure, a recent UN report said.
Last week, Seoul sent $8 million through two UN agencies as food aid for children and pregnant women in the neighbouring country and has been discussing sending donations with the World Food Programme.
In an interview with the news agency, Quintana questioned the tough international sanctions on Pyongyang for its weapon tests as they were impacting its population due to food crisis.
During his visit, the rapporteur will also address a press conference on Friday to provide details of the visit. The outcome of the visit will be included in a report he will present to the UN General Assembly.
North Korea has never allowed Quintana access to its territory and has avoided direct contact with his office since he took charge in 2016.
N Korea often figures in lists of nations with the worst human rights records. A 2014 report by a UN special commission flagged killings, slavery, disappearances, summary executions, torture, sexual violence, forced abortions, food deprivation, forced displacement of people and political, religious or gender-based persecution as common practices in the country.
( With inputs from IANS )