2017 K3 League Basic

The 2017 K3 League Basic was the first season of the K3 League Basic.

The second division of the K3 League was founded in the name of "K3 League Basic" in 2017, and the bottom eight teams of the 2016 K3 League participated in its inaugural season. Newly formed clubs Busan FC and Pyeongtaek G-SMATT also joined it.

After the regular season, champions were promoted to the first division "K3 League Advanced" and four teams from second to fifth-placed team qualified for the promotion playoffs.

Teams
Yeonggwang FC withdrew from the K3 League Basic after becoming one of eignt teams relegated from the K3 League.

Promotion playoffs
When a match was finished as a draw, its winners were decided on the regular season rankings without extra time and the penalty shoot-out.