Intercultural sensitivity is the affective dimension of intercultural competence. Recently, the Intercultural Sensitivity Scale (ISS) was validated for Korean samples, which raised conceptual, translational, and metrological problems. This study improved on the previous ISS Korean version, developed the Respect for Diversity Scale (RDS), and reanalysed the results according to gender and school level. The sample comprised 542 native Korean-speaking high school and college students. Both scales confirmed the validity of 12 items across four dimensions. Notably, the mean ISS scores exceeded those of the RDS across most factors. Gender differences exhibited significance in the scores of both scales, while school-level differences did not prove significant. This study contributes to the literature that has adapted and validated the ISS with participants from non-English-speaking cultures. Additionally, it sheds light on the relationship between the ISS and measures of general diversity appreciation, highlighting variations based on participants' background characteristics.