The invention belongs to the field of fluid machinery and relates to a porous structure type light impeller. The porous structure type light impeller comprises a wheel disc and blades which are fixed to the wheel disc, wherein the inner part of the wheel disc is designed into a porous structure. By adopting the porous structure, materials can be saved, the mass of the impeller can be reduced, the centrifugal force load of the impeller can be reduced; and at the same time, by utilizing walls among holes, centrifugal force at the periphery of the impeller can be transferred and dispersed to the axis or axle hole direction, and the stress distribution of the whole impeller is more uniform and reasonable. Under the condition of using the same manufacturing materials, working can be carried out at a higher linear speed, the performance of the impeller is improved, and a technical foundation is provided for developing the high-performance impeller.