A molding machine for a thermoplastic resin composition configured to melt a thermoplastic resin composition including a first thermoplastic resin and to mold the thermoplastic resin composition into a strand shape, the molding machine comprising: a supply port configured to supply the thermoplastic resin composition; a melting and kneading part configured to melt and to knead the thermoplastic resin composition supplied from the supply port; a resin reservoir part configured to retain the thermoplastic resin composition melted and kneaded in the melting and kneading part; and a discharge part configured to discharge in a strand shape the thermoplastic resin composition retained in the resin reservoir part; wherein the resin reservoir part has a shape tapering from the melting and kneading part toward the discharge part; characterized in that the tapered shape in the resin reservoir part is configured such that: a ratio (A2 to A1) of a cross-sectional area A2 of a flow path for resin in a second connection part between the resin reservoir part and the discharge part, to a cross-sectional area A1 of a flow path for resin in a first connection part between the resin reservoir part and the melting and kneading part, is 1% to 50%; and in a length L1 from the first connection part to the second connection part, with the cross-sectional area A1 as a reference, the cross-sectional area of the flow path for the resin in the resin reservoir part decreases in a range from 0.1 to 2.0%/mm. a supply port configured to supply the thermoplastic resin composition; a melting and kneading part configured to melt and to knead the thermoplastic resin composition supplied from the supply port; a resin reservoir part configured to retain the thermoplastic resin composition melted and kneaded in the melting and kneading part; and a discharge part configured to discharge in a strand shape the thermoplastic resin composition retained in the resin reservoir part; wherein the resin reservoir part has a shape tapering from the melting and kneading part toward the discharge part; characterized in that the tapered shape in the resin reservoir part is configured such that: a ratio (A2 to A1) of a cross-sectional area A2 of a flow path for resin in a second connection part between the resin reservoir part and the discharge part, to a cross-sectional area A1 of a flow path for resin in a first connection part between the resin reservoir part and the melting and kneading part, is 1% to 50%; and in a length L1 from the first connection part to the second connection part, with the cross-sectional area A1 as a reference, the cross-sectional area of the flow path for the resin in the resin reservoir part decreases in a range from 0.1 to 2.0%/mm. a ratio (A2 to A1) of a cross-sectional area A2 of a flow path for resin in a second connection part between the resin reservoir part and the discharge part, to a cross-sectional area A1 of a flow path for resin in a first connection part between the resin reservoir part and the melting and kneading part, is 1% to 50%; and in a length L1 from the first connection part to the second connection part, with the cross-sectional area A1 as a reference, the cross-sectional area of the flow path for the resin in the resin reservoir part decreases in a range from 0.1 to 2.0%/mm.