This paper reported a novel hybrid PCM-based heat sink that combines the active flow channel, passive natural convection, and PCM latent heat absorption to maintain the temperature control performance while electronic devices are subjected to the transient pulsed heat flux shock. Moreover, the effects of the channel's flow characteristics, flow channel height, and heat flux on the heat dissipation and temperature management features are analyzed numerically. In addition to the thermal characteristics, the energy consumption efficiency of the hybrid system is also discussed. The results demonstrate that the effective temperature control performance of the passive PCM-based heat sink increases with the rise of impact heat flux until it is <8 W·cm−2, and the temperature control efficiency can reach 47.6 % compared with the passive heat sink without PCM. Adopting the active flow channel performs excellently in temperature control management as ultra-high heat flux is applied; meanwhile, the pumping power should be considered. The novel hybrid PCM-based heat sink designed in this work with Hc = Hf/15 and Re = 150 excelled over the traditional pure channel heat sink with Hc = 5Hf/15 and Re = 2250. Moreover, the temperature control performance and energy-saving effect were both improved after optimization, and the energy-saving rate reached approximately 83.3 %.