Leader Kim Jong Un took part in the ceremony, the report said, as well as a number of senior government officials including Kim Tok Hun, premier of the cabinet.
The milestone comes two months after Kim broke ground in February on another housing project that has been described as "another luxurious street of socialism full of the people's happiness" by KCNA.
In 2021, North Korea announced plans to build 50,000 new apartments in the capital over the course of five years.
Since then, North Korea said it has moved forward with a series of construction projects, some of which are still ongoing amid foreign suspicion of food shortages.
Kim said the housing project is a long-cherished plan being pushed forward as a "top priority" by the Workers' Party of Korea and the state and he reaffirmed his idea to make Pyongyang a "world-famous" city, according to KCNA.