On 12 June 1961 in Gornji Milanovac, by the initiative of former FK Takovo footballer Miroslav Spasojević, was held the first foundational assembly of the newly created football club. The assembly was attended by the sindical union members of the companies "Graditelj" and "Metalac" and they suggested that the workers of the city companies should actively play football in the club. The club was founded as FK Radnik and the club management was elected. The presidents of the companies "Metalac" and "Graditelj" were elected president and vice-president respectively. The coaching position was attributed to Miroslav Spasojević, nicknamed "Era", who was also the team captain and main player. The club started competing within the league of the football association of Čačak. In the 1963–64 season, FK Radnik won the championship and got promoted. At the end of the 1964–65 season, by the initiative of the general manager of "Metalac" company, Milan Mišović, the club changed its name into FK Metalac, and the company begins to support financially the club. The new club president was Veljo Perišić and a new age begins for the club. In 1968, the club is promoted to the Western Morava League ("Zapadnomoravska Liga"), in 1970 is promoted to the Morava-Šumadija League ("Moravsko-šumadijska Liga") and again two seasons later, the club starts competing in the Serbian League South, Yugoslav fourth tier back then. In that period the club also won the Serbian Cup by winning FK Rudar Kostolac by 4–0, and reached the 1/16 finals of the Yugoslav Cup where they lost after extra-time in Travnik against NK Borac Travnik (today NK Travnik) by 1–2.