2018 K3 League Basic

The 2018 K3 League Basic was the second season of the K3 League Basic. Yeoju Sejong and Chungju Citizen joined the league in this season. The top two teams were directly promoted to the K3 League Advanced, and third, fourth and fifth-placed team qualified for the promotion playoffs.

Team changes
Relegated from K3 League Advanced
 * Paju Citizen
 * Yangju Citizen

Promoted to K3 League Advanced
 * Seoul Jungnang
 * Pyeongtaek Citizen

Newly joined
 * Yeoju Sejong
 * Chungju Citizen

Promotion playoff
When the match was finished as a draw, its winners were decided on the regular season rankings without extra time and the penalty shoot-out. Therefore, Chungju Citizen was promoted to the K3 League Advanced after the draw.