The present disclosure relates to a preparation method of a porous super absorbent polymer exhibiting excellent absorption performance and improved absorption rate due to a novel pore structure, and a porous super absorbent polymer prepared therefrom. The porous super absorbent polymer includes a base resin powder including a cross-linked polymer of a water soluble ethylene-based unsaturated monomer containing acidic groups which are at least partially neutralized, and an inorganic filler contained in the cross-linked structure of the cross-linked polymer, wherein the base resin powder includes a plurality of pores having a diameter of a sub-micron (sub- µ m) scale in the cross-linked structure, and an interconnected pore structure in the form of an open channel in which 90% or more of the pores are connected to each other.
