The present invention provides a filament for material extrusion 3D printer molding, which affords a molded article having soft texture and excellent heat resistance and among others, exhibits good moldability in molding by a material extrusion 3D printer. The present invention relates to a filament for material extrusion 3D printer molding, including a thermoplastic elastomer which contains at least a specific block copolymer and in which the ratio between storage modulus and loss modulus measured at 200° C. and 100 Hz by dynamic viscoelasticity measurement is in a specific range.