1. Slovenski Športni Klub Maribor (English: First Slovene Sports Club Maribor) or simply I. SSK Maribor was a football club from Maribor. The club was founded in 1919. Drago Kolbl was the first president of the club. I. SSK Maribor had a fierce rivalry with NK Železničar Maribor.
The club was founded on 28 June 1919 by Ivo Vauda, who was the best Slovenian footballer in Maribor at the time. I. SSK Maribor was considered as the successor of ŠD Maribor. The first match was played on 11 July 1919 against the German-based team from Maribor, Hertha. I. SSK Maribor won the game 2–1. The first official match in the Slovenian Republic League was played against another German-based team from Maribor, Rapid Marburg. Rapid won the first game 5–0, but in the second game, I. SSK Maribor won 2–1. The first international match was played on 1 July 1922 against Grazer AK. The match ended with a draw, 2–2. After finished as the runners-up on six occasions, they finally won the league for the first time in the 1930–31 season. They won another two titles in the 1932–33 and 1938–39 seasons. The club was dissolved at the beginning of the World War II in Yugoslavia.
The club did not have its own ground until 1920, when the players helped to create a football pitch at the Ljudski vrt.