Abstract: To investigate the flow boiling pressure drop and comprehensive performance comparison in mini channel under the combined effects of phase separation structures and pulsating pressure, ethanol was used as the working fluid, and poly（vinylidene fluoride-co-hexafluoropropylene） （PVDF-HFP-F） porous membranes were used as gas-liquid phase separation tools. Flow boiling experiments were conducted in co-current and counter-current mini channel with different numbers of pores （10, 20, and 30） in the phase separation structures, under inlet temperature of 40 ℃, average mass flux ranging from 68.89 to 192.89 kg·（m²·s）⁻¹, and heat flux ranging from 69.7 to 125.07 kW·m⁻², under different pulsating pressure conditions. The pressure drop characteristics and Ledinegg instability in mini channel were studied under pulsating pressure alone and under the combined action of pulsating pressure and phase separation structures with different pore numbers. The comprehensive boiling heat transfer performance of the mini channel was evaluated using the Performance Evaluation Criterion （PEC） under the combined action of phase separation structures and pulsating pressure. The results showed that under the combined effects of phase separation structures and pulsating pressure, the two-phase frictional pressure drop per unit channel length was reduced by up to 37.97% compared to that under pulsating pressure alone, and the absolute value of the negative slope in the two-phase boiling region of the total pressure drop–flow rate curve was reduced by up to 48.17%. The maximum PEC value reached 1.980.