The working-level dialogue began shortly after 10 a.m. (Seoul time) on the RoK side of the joint security area (JSA), also known as Panmunjom, according to the RoK presidential office Cheong Wa Dae.
The meeting comes a week after the two Koreas agreed to hold the summit on April 27 in a high-level dialogue held on the DPRK side of the JSA.
The summit between RoK President Moon Jae-in and DPRK leader Kim Jong-un will also be held at the JSA, which is located inside the DMZ that divides the two Koreas.
Two Koreas remain technically at war, as the 1950-53 Korean War ended with an armistice and not a peace treaty.
April 5's meeting is largely aimed at discussing security measures, protocols and media coverage, Cheong Wa Dae officials said.
The talks are to be followed by a separate working-level meeting on April 7 to discuss the establishment of a communication hotline between the two Korean leaders, which the countries have agreed to install.
The two Koreas summit, if held, will mark the third of its kind and will also be the first time since the end of the Korean War. The first two inter-Korean summits were both held in Pyongyang in 2000 and 2007.
The proposed summit follows a flurry of dialogue and exchanges between the two Koreas around the PyeongChang Winter Olympic and Paralympic Games in RoK earlier this year.
Moon's top security advisor, Chung Eui-yong, traveled to Pyongyang early last month to meet the reclusive DPRK leader and reach an agreement on the inter-Korean summit, as well as on a US-DPRK summit.
US President Donald Trump has said he will meet DPRK's Kim in May. The date and location of the U.S-DPRK summit have yet to be decided.