["Japanese Psychological Research, EarlyView. ", "\nAbstract\nThis study aimed to adapt the 8‐Item Growth Mindset Scale into Turkish and evaluate its psychometric properties through a three‐stage study. In Study 1 (Mage = 29.84 years, SD = 11.2 years) and Study 2 (Mage = 29.26 years, SD = 11.7 years), involving 1,344 participants, a one‐factor structure was confirmed with high internal consistency (α = .87, ω = .87) through exploratory and confirmatory factor analyses. Furthermore, convergent validity, predictive validity, and test–retest reliability were examined. Study 3 with 590 participants aged between 18 years and 67 years (Mage = 27.68 years, SD = 10.8 years) further ensured the linguistic proficiency and cultural representativeness of the scale in the Turkish context. Findings support the Turkish version as a reliable and valid tool for assessing growth mindset in adults. The findings have implications for practice, particularly for the development and evaluation of growth mindset‐based interventions in educational and clinical settings. The study contributes to the growing literature on growth mindset assessment in diverse cultural contexts, complementing prior work in Japanese samples.\n"]