2017–18 Mohun Bagan A.C. season
The 2017–18 Mohun Bagan A.C. season is the 128th season of Mohun Bagan A.C. since the club's formation in 1889 and their 11th season in the I-League which is India's top football league. They finished 2nd in the table in the Calcutta Football League and finished 3rd in the I-League.
Sanjoy Sen resigned as the coach of Mohun Bagan on 2 January 2018 following three home draws and a defeat against Chennai City placing the team in 4th position, virtually ending their title hopes. Shankarlal Chakraborthy was appointed as head coach for the remainder of the season.
Their title hopes however did stay intact till the last fixture of the season where they could've won the title had other results gone in their favour, but it wasn't too be and Minerva Punjab ultimately clinched the title. Although the 2017–18 season was not an ideal season for the club after a loss of form and change of coach midway through the season along with injuries to important players like Sony Norde and Yuta Kinowaki, they did manage to win both the home and away fixtures against arch rivals East Bengal.
Sponsor
As of 3 December 2017| Sponsors Type | Sponsor's Name |
| Sponsor | |
| Co-Sponsor | M.P Birla Cement, Nilkamal, Floral, Ripley |
| Kit Sponsor | Shiv Naresh |