Jong made her decisive move close to the stadium, building a lead of several metres over Japanese runner Ari Ichihashi. The 25-year-old North Korean easily beat her personal best, finishing in 2hr 26min 59sec.
"Yes, I am the new marathon runner in the eyes of the rest of the world." she said. "Hopefully they will know me better in the future."
Ichihashi also improved her previous best, taking the silver medal in 2:27.02, while Romania's Lidia Slavuteanu-Simon produced a storming finish to win bronze in 2:27.41.
Olympic champion Fatuma Roba of Ethiopia broke away from a leading group of four featuring the eventual medal winners with around eight kilometres remaining, but she was soon caught and ended fourth.
Unlike the top two medallists, Slavuteanu-Simon was one of the pre-race favourites. She finished third at the last world championships in 1997 in Athens and won the Osaka marathon in February this year.
"I had stomach problems at halfway." she said. "Because of that I couldn't follow as the three picked up the pace. Luckily I recovered and could speed up to capture the bronze."
Jong's previous best performance was her second place in the Pyongyang marathon in 1996. She finished 20th at the Atlanta Olympics that year.
"Even when the leading group was still together at about two hours I was confident that I could break away successfully." she said.Reuse content