1. Liga

In sports, '''1. Liga, 1. liga, I Liga or Erste Liga''' may refer to:

Association football

 * 1. līga, football league in Latvia
 * I liga, football league in Poland
 * 1. Liga Promotion, the third tier of the Swiss football league system
 * 1. Liga Classic, the fourth tier of the Swiss football league system
 * 1. Liga (Slovakia), former name of the second-highest football division in Slovakia
 * Austrian Football First League, (German: Erste Liga), the second highest division in Austrian football league system
 * Czech First League, the top tier of the Czech football league system

Ice hockey

 * Czech 1. Liga, second-highest ice hockey division in the Czech Republic
 * Polish 1. Liga, second-highest ice hockey division in Poland
 * Slovak 1. Liga, second-highest ice hockey division in Slovakia
 * Swiss 1. Liga (ice hockey), third-highest ice hockey league in Switzerland
 * Erste Liga (ice hockey), an international ice hockey league

Basketball

 * I Liga (basketball), second level basketball league in Poland

Rugby

 * I liga Rugby, second-highest rugby union league in Poland