In order to improve the energy recovery efficiency of accumulator in elevator system, a new hydraulic flywheel accumulator was proposed which combined hydraulic accumulator with flywheel accumulator. The simulation model of the hydraulic flywheel accumulator was established by using AMESim, and it was applied to the new elevator system. The results show that the total recovered kinetic energy of the hydraulic flywheel accumulator can reach 100 kJ, the energy density can be increased to 4.02 W·h/kg, the displacement and pressure change are relatively gentle, and the working performance is stable.