Theoretical models and empirical studies have long assumed that the positive association between teacher self-efficacy (TSE) and job satisfaction (JS) is invariant regardless of any teacher factors and that TSE predicts JS. Using OECD TALIS 2018 data and a three-time point longitudinal Croatian data, we test these assumptions by examining the invariance of the association between TSE and JS across four factors (gender, career stage, educational levels, and time) and the causal ordering of the two constructs. We find support for the first assumption but not the second; that is, JS predicts TSE and TSE does not predict JS.