The purpose of this study was to explore the causes of psychometric heterogeneity of Spiritual Change factor in Posttraumatic Growth Inventory(PTGI), which is the measurement most worldwide-used in PTG related-research. In study 1-1, Data were collected from 273 Korean adults, who rated the levels of perceiving each PTGI item as growth. As the results of analyses, the factor structure of PTGI was not equivalent across the religiosity. The group with religiosity more significantly perceived the Spiritual Change domain than the group with no religiosity. The relationship between experiences and perceptions of PTG also varied between two groups. Study 1-2 aimed to compare the influence of spiritual change on happiness depending on the context of religiosity. The results showed while spiritual change significantly influenced on happiness in the group with religiosity, not in the other group. Based on the overall findings, the clinical implications of the current study regarding the cross-cultural differences in the perceptions of PTG were discussed.