Turbofan engine nozzle ejector technology was used for the design of a new turbine for efficient utilization of low-grade wind energy and ocean current energy. The turbine was composed of a low-rotation-speed single-stage and a lobed ejector. A parameterized method for building the lobed ejector structure was given. Reynolds-averaged NS equations and k-ε turbulence model were chosen for numerical study on the aerodynamic performance and ejection ability of the turbine using commercial software CFX. Simulation results indicated the lobed ejector could bring the wind/oceans currents energy into the back of turbine, the stream-wise vortices and normal vortices behind the lobes were produced to pump the low speed fluid behind the turbine. The effect could make the pressure reduced, the effective velocity almost increased 1.4 times, and the energy grade was improved. In the condition of wind speed ranges from 2 to 6 m/s and ocean current speed ranges from 2 to 4 m/s, the power output of the turbine exponentially increased as the flow velocity increased, and flow capacity was increased by 32.70% -35.33% than single-stage turbine. The energy utilization efficiency of the turbine went up to 66%-77%.