2018 Vietnamese National Football Second League

The 2018 Vietnamese National Football Second League was the 20th season of the Vietnamese National Football Second League. The season began on 25 April 2018 and finished on 15 July 2018.

Rule changes
In this season, there are 13 teams divided in two groups in qualifying stage according to geographic region. The top 2 teams of each group will be qualified to final round. In final round, 4 teams will play 3 matches:
 * Match 1: 1A vs 2B
 * Match 2: 1B vs 2A
 * Match 3: Match 1 loser vs Match 2 loser

The winners of each match will promote to 2019 V.League 2. There are no teams relegated to 2019 Vietnamese Third League.

Team changes
The following teams have changed division since the 2017 season.

To Vietnamese Second League
Promoted from Vietnamese Third League Relegated from V.League 2 Team transfer
 * Bà Rịa Vũng Tàu
 * Nam Định B
 * Vĩnh Long
 * Quảng Ngãi
 * None
 * Fishsan Khánh Hòa (transferred from Cà Mau)
 * Phố Hiến (transferred from PVF)

From Vietnamese Second League
Relegated to Vietnamese Third League Promoted to V.League 2 Team transfer Withdrew
 * Sanatech Khánh Hòa
 * Công An Nhân Dân
 * Bình Định
 * Hà Nội B
 * Cà Mau (transferred from Fishsan Khánh Hòa)
 * PVF (transferred from Phố Hiến)
 * Viettel B
 * Quảng Ngãi
 * Mancons Sài Gòn

Match 1
An Giang promoted to 2019 V.League 2.

Match 2
Phù Đổng promoted to 2019 V.League 2.

Match 3
Phố Hiến promoted to 2019 V.League 2.