Method for producing foam blow molded body, and foam blow molded body

A method for producing a foamed blow-molded article, the method comprising:

• a step of blow-molding a foamed parison obtained by foaming a mixed resin comprising a polyolefin-based resin (A) and an olefin-based thermoplastic elastomer (B), wherein
• the polyolefin-based resin (A) comprises a branched homopolypropylene (a1) and a linear block polypropylene (a2), and a mass ratio [(a1):(a2)] of the branched homopolypropylene (a1) to the linear block polypropylene (a2) is 50:50 to 93:7,
• the olefin-based thermoplastic elastomer (B) is a hydrogenated product of a triblock copolymer comprising a crystalline olefin polymer block and a polymer block of a conjugated diene compound, and
• in the mixed resin, a blending amount of the olefin-based thermoplastic elastomer (B) with respect to 100 parts by mass of the polyolefin-based resin (A) is 20 parts by mass or more and 40 parts by mass or less.