A thermoplastic fluororesin composition comprising: a thermoplastic fluororesin having a Shore D hardness of less than or equal to 50, the Shore D hardness being measured at 23°C in accordance with ASTM D2240; a cross-linked structure forming agent that is selected from the group consisting of a polyamine compound (b-2), and a polyhydroxy compound (b-3) and that is capable of forming a cross-linked structure through a reaction with the thermoplastic fluororesin, and a cross-linkable rubber component, wherein a content of the cross-linkable rubber component is less than or equal to 100 parts by weight per 100 parts by weight of the thermoplastic fluororesin, the thermoplastic fluororesin composition not substantially containing an acid acceptor when containing the polyamine compound (b-2), and not substantially containing at least one of the acid acceptor and an onium compound when containing the polyhydroxy compound (b-3), wherein term "cross-linked structure forming agent" refers to a reagent that is capable of forming a cross-linked structure together with the thermoplastic fluororesin through a reaction with the thermoplastic fluororesin by irradiation with an ionizing radiation, the phrase "does not substantially contain an acid acceptor" means that the content of the acid acceptor is less than or equal to 0.1 parts by weight per 100 parts by weight of the thermoplastic fluororesin, and the phrase "does not substantially contain at least one of an acid acceptor and an onium compound" means that the content of at least one of the acid acceptor and the onium compound is less than or equal to 0.1 parts by weight per 100 parts by weight of the thermoplastic fluororesin. a thermoplastic fluororesin having a Shore D hardness of less than or equal to 50, the Shore D hardness being measured at 23°C in accordance with ASTM D2240; a cross-linked structure forming agent that is selected from the group consisting of a polyamine compound (b-2), and a polyhydroxy compound (b-3) and that is capable of forming a cross-linked structure through a reaction with the thermoplastic fluororesin, and a cross-linkable rubber component, wherein a content of the cross-linkable rubber component is less than or equal to 100 parts by weight per 100 parts by weight of the thermoplastic fluororesin, the thermoplastic fluororesin composition not substantially containing an acid acceptor when containing the polyamine compound (b-2), and not substantially containing at least one of the acid acceptor and an onium compound when containing the polyhydroxy compound (b-3), wherein term "cross-linked structure forming agent" refers to a reagent that is capable of forming a cross-linked structure together with the thermoplastic fluororesin through a reaction with the thermoplastic fluororesin by irradiation with an ionizing radiation, the phrase "does not substantially contain an acid acceptor" means that the content of the acid acceptor is less than or equal to 0.1 parts by weight per 100 parts by weight of the thermoplastic fluororesin, and the phrase "does not substantially contain at least one of an acid acceptor and an onium compound" means that the content of at least one of the acid acceptor and the onium compound is less than or equal to 0.1 parts by weight per 100 parts by weight of the thermoplastic fluororesin.