The Career Adapt-Abilities Scale (CAAS) has been validated in several East Asian countries, but the measurement equivalence of its four dimensions and construct validity has not yet been evaluated in Japan. Results from Japanese (n = 298) and South Korean (n = 301) college students indicated good to excellent internal consistency estimates, and configural and metric invariance, confirming the factor structure across the groups. Item intercepts across samples, however, were scalar noninvariant, preventing comparison of mean scores. Results also provided support for criterion-related validity of CAAS scores. This model for measuring career adaptability can apply to the Japanese college context.