RESIN FOAMED BODY

A resin foamed body 1 is a resin foamed body made of flexible resin, the resin foamed body entirely includes a skeleton part 2, the skeleton part includes a plurality of bone parts 2B and a plurality of connection parts 2J connecting end parts of a plurality of bone parts, and an average value AV(A0/A1) of a ratio AO/A1 of cross-sectional area A0 of a bone change part of each bone part at an edge 2B22 on a bone constant part side relative to cross-sectional area A1 of the bone change part at an edge 2B21 on the connection part side satisfies 0.15≤AVA0/A1