The first football was brought to Prijedor in 1918 by Sveto Radetić, Stevan Mitrinović and Pero Čanak, who bought the ball from Austria.

The match ended with a 2–1 victory for Rudar, and the players in that match were Branko Bjekić, Sadik Burazerović, Milan Prerad, Ivan Sedlaček, Toni Hribar, Drago Nedić, Poldek Mastinjak, Jovo Gvozden, Tone Vikić, Josip Brečević and Božidar Veslić.

The club didn't compete during the economic crisis between 1931 and 1933 when the mine was almost shut down, with many miners being left without work and in hard living conditions.

In this period it is worthwhile to mention the special contribution and financial support provided to the club and its players by Mr. Dr. Mladen Stojanović, a longtime mdoctor in the mine, a humanist and afterwards a leader of the Partisans from Kozara during WWII.

The players that made this possible were: Izetagić, Bevandić, Baškot, Mustedanagić, Miljević, Radinović, Dervić, Bećarević, Bekan, Porobić and Gombović.

In 1970 Rudar reached the 1/16 final of the Yugoslav Cup playing in its first ever TV-transmitted match, against top league OFK Belgrade.

Rudar lost 0–2 and the players that played that match were: Janković, Omerbašić, Porobić, Talić, Milijević, Okanović, Ličina, Damjanović, Torić, Bevandić i Gombović.

In this generation are found players like: Janković, Hidić, Vukelja, A. Bašić, Porobić, Škondro, Gombović, Vidović, Ličina, Mandić, Bevandić, Damjanović and Crnkić.

In December 1979 an entire generation of footballers that provided much success for the club played their fairway match Miroslav Janković, Ivo Baškarada, Omer Bašić, Kemal Porobić, Ante Gombović, Nikola Bevandić, Simo Damjanović, Slobodan Ličina, Aki Bašić, Emsud Ramulić and Ibrahim Okanović-Špico.

In the season 1983/84 Rudar returned to the Second League, and the players that earned this promotion were: Sead Rešić, Vitomir Samardžija, Muhamed Cerić, Sabid Sadiković, Vinko Škondro, Mladen Parhamov, Vinko Samardžija, Goran Pekija, Zoran Vuković, Mirzet Bejzurić, Zlatko Abdulović, Fahrudin Bihorac, Edin Begović, Mladen Ćulum, Ilija Marin, Žarko Mandić, Bajram Zgog, Novo Bešević, reserves Panić, Hrvat, Duratović, and the coach Nikola Bevandić.

In 1987/88 the club missed just one point and didn't qualify for the newly formed unified Yugoslav Second League by a goal difference.

The second hand, played in Prijedor in front of a 6,000-spectator crowd, ended up with Rudar winning by same result, 1–0, Bijaljac being the scorer of the lone goal.

The following players managed this promotion: Kondić, Despotović, Dobrijević, Muzgonja, Ilinčić, Kovačević, Brkić, Stijepić, Kantar, Golić, Kecman, Dašić and Kotoran.