The population of Poland could be of particular interest to researchers studying religion and spirituality. Catholicism has played a significant role in shaping the country's culture, history, and tradition and is considered a national religion. More recently, however, the processes of moving away from regular participation in religious services and loosening ties with the institution of the Catholic Church are marked (Polish Public Opinion Research Center, CBOS). The Polish Catholic setting may modify the associations between psychological variables that have been studied in their relationships with spirituality, which have been investigated in religious contexts differing from a PolishCatholic one. Given this context, we examined the internal structure of spiritual well-being in the sample of present-dayPolishCatholics (Study 1) and how spiritual well-being is related to mental health (Study 2). The internal structure of the Spiritual Well-Being Scale was replicated in the Polish sample, but only positively worded items loaded on the Religious and Existential Well-Being subscales. Spiritual well-being was positively related to positive mood, satisfaction with life, and psychological well-being; it wasnegatively associated with negative mood, depression, and anxiety, thus remaining significantly related to psychological well-being among Polish Catholics.