|Number of teams||8|
|Relegation to||I-League 2nd Division|
|Level on pyramid||1|
|Domestic cup(s)|| Federation Cup|
|AFC cup(s)|| AFC Cup|
AFC Champions League (Qualifying play-off)
|Current champions||Aizawl F.C. (1th title) (2016–17)|
|Most successful club|| Dempo|
The I-League, officially known as the Hero I League due to sponsorship reasons, is an Indian professional league for men's association football clubs. Contested by 7 clubs (currently), it operates on a system of promotion and relegation with the I-League 2nd Division as well as a system of direct-entry.
Seasons run from January to May, with teams playing 18 matches each, totalling 90 matches in the season. Most games are usually played in the afternoons during the weekends or midweeks. It is currently sponsored by Hero.
The competition, formed as the ONGC I-League in 2007 in an effort to professionalize the game in India after holding the old National Football League for eleven seasons, replaced the NFL as the primary competition in the country. The league's first official broadcaster was Zee Sports. The first goal for the league was to have 16 teams by the third season, by which the league would be spread all around India.
Since the league inception, a total of five clubs have been crowned champions of the I-League. Of the 25 clubs to have competed since the inception of the I-League in 2007, the teams that have won the title are Mohun Bagan A.C. (once), Bengaluru FC (twice), Churchill Brothers (twice), Dempo (thrice), and Salgaocar (once) respectively. The title has only been won thrice by a team from outside of the state of Goa with the first six of eight editions of the league being won by Goan sides. The current champions of the I-League are Bengaluru FC, who won their second league title in three years.
After the 2015–16 I-League season, newly promoted Aizawl were relegated. Three-time I-League champions Dempo who were relegated in 2014–15 season, earned a promotion again as the winner of 2015–16 I-League 2nd Division.
On 24 June 2016, Salgaocar and Sporting Goa announced their withdrawal from the league. However, on 26 September 2016, the All India Football Federation announced that they would reinstate Aizawl back into the I-League, despite relegation the previous season.
|Aizawl||Rajiv Gandhi Stadium||5,000|
|Bengaluru FC||Sree Kanteerava Stadium||24,000|
|DSK Shivajians||Balewadi Sports Complex||22,000|
|East Bengal||Salt Lake Stadium||68,000|
|Mohun Bagan||Salt Lake Stadium||68,000|
|Shillong Lajong||Jawaharlal Nehru Stadium||30,000|
|National Football League|
|I-League 2nd Division|
|I-League stadiums 2016-17|
Barasat Stadium · Duler Stadium · Fatorda Stadium · Jawaharlal Nehru Stadium · Kalyani Stadium · Salt Lake Stadium · Shree Shiv Chhatrapati Sports Complex · Sree Kanteerava Stadium · Tilak Maidan Stadium
|Indian competitions · Indian coaches · Indian players · Indian stadiums|
|Football in India|
|Top level football leagues of Asia (AFC)|
Afghanistan · Australia · Bahrain · Bangladesh · Bhutan · Brunei · Cambodia · China PR · Chinese Taipei · East Timor · Guam · Hong Kong · India · Indonesia · Iran · Iraq · Japan · Jordan · Kuwait · Kyrgyzstan · Laos · Lebanon · Macau · Malaysia · Maldives · Mongolia · Myanmar · Nepal · North Korea · Northern Mariana Islands† · Oman · Pakistan · Palestine: Gaza Strip–West Bank · Philippines · Qatar · Saudi Arabia · Singapore · South Korea · Sri Lanka · Syria · Tajikistan · Thailand · Turkmenistan · United Arab Emirates · Uzbekistan · Vietnam · Yemen