The Catholic Action of the Łomża’s Diocese was erected in 1931, and functioned until 1939, ie. to the moment of the Second World War outbreak. It had well–organized structures, and realized a wide scale activity of religious, economical, cultural, educational (etc.) character. There was put a particularly great accent on its formative work. It was recognized as a crucial condition to any influence of the Catholic Action. There was used a vast range of the materials and formative means such as: statutes, watchwords, programs, periodicals, and books’ issues. The main purpose of the article is an analysis of those materials, and an answer to the following question: how much were the presented materials used by the particular departments of C.A., and what influence had they got on the C.A. activity?