To provide polypropylene-based resin expanded particles capable of giving the expanded formed body which has cell diameters of a considerable uniformity and is excellent in the surface external appearance, mechanical physical properties, fusibility between the expanded particles and also a high heat-resistant temperature.

The polypropylene-based resin expanded particle has a cover layer and a core layer in the expanded state, whose core layer is constituted with the base resin having (a) a structural unit derived from polypropylene of 100-85% by mole and a structural unit derived from ethylene and/or a 4-20C α-olefin of 0-15% by mole and (b) a ratio of 2,1-insertion- based position irregular units to the whole inserted propylene monomer units of 0.5-2.0% and a ratio of 1,3-insertion-based position irregular units similarly thereto of 0.005-0.4% on the basis of a measurement with 13C-NMR.

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