RU-38 was established in Pori in 1938 by Oy W.Rosenlew Ab.

The sections of the club included football from the start but it didn't play any games until 1947.

Arguably RU-38's best players in the 50s were Stig-Göran Myntti, Matti Jokinen and Seppo Pelkonen.

RU-38 was promoted to the Mestaruussarja, the top tier of football at the time, in 1959.

The first season was a success as the team was placed 2nd in the series.