This paper develops and estimates a new Keynesian (NK) model with endogenous technology. It shows that introducing endogenous technology can solve three important puzzles faced by conventional NK models: the “inflation persistence”, “disinflationary news shock”, and “zero lower bound (ZLB) supply shock” puzzles. First, the observed persistence in inflation is explained without relying on the conventional NK models' additional assumptions, e.g., backward price indexation. Second, it explains the observed disinflationary effect of a news shock. Third, the model avoids the conventional NK models' paradoxical, empirically inconsistent prediction that a negative supply shock is expansionary at the ZLB on interest rates.