Provided are a short-circuit protection method and device for a half-bridge resonance converter. The method includes: a secondary-side current signal of the half-bridge resonance converter is detected, and the detected secondary-side current signal is converted into a corresponding first sampling voltage signal; whether a cycle-by-cycle protection is required in accordance with the first sampling voltage signal is determined; and a driving signal of the half-bridge resonance converter is compulsorily blocked during a preset cycle, if the cycle-by-cycle protection is required. Short-circuit protection may be performed for the half-bridge resonance converter, meanwhile a power density of the half-bridge resonance converter is satisfied.