A coupling/uncoupling mechanism (10A, 10B, 10C), employed for coupling and uncoupling two couple-able sections to and from each other, comprising a bar-shaped male coupling body and a female coupling body having an insertion space for inserting and withdrawing the male coupling body, wherein said female coupling body comprises: a support member having a support side section, which is in parallel with the insertion space so as to support a state in which said male coupling body is inserted in said insertion space; and a lever member, provided in a position facing said support side section to form said insertion space interposed therebetween, and having one end and the other end, said one end being connected to said support member, said other end being configured to be movable in a direction toward a side opposing to said insertion space by the lever support-coupling section; characterized in that said female coupling body further comprises: a lever-fixing member for providing fixing so as to prevent the other end of said lever member from being moved to the outside by connecting the other end of said lever member with said support side section at the both ends, wherein an insertion hole for inserting one end of said lever-fixing member is further provided in said support side section or the other end of said lever member, and an insertion hole-heating unit disposed in a position adjacent to the insertion hole, for heating the interior of the insertion hole, is further provided, and wherein, when said male coupling body is coupled to the female coupling body, said end section of said support side section is connected to the other end of said lever member by blocking the insertion hole with a thermoplastic material, after one end of said lever-fixing member is inserted in said insertion hole. a support member having a support side section, which is in parallel with the insertion space so as to support a state in which said male coupling body is inserted in said insertion space; and a lever member, provided in a position facing said support side section to form said insertion space interposed therebetween, and having one end and the other end, said one end being connected to said support member, said other end being configured to be movable in a direction toward a side opposing to said insertion space by the lever support-coupling section; a lever-fixing member for providing fixing so as to prevent the other end of said lever member from being moved to the outside by connecting the other end of said lever member with said support side section at the both ends, wherein an insertion hole for inserting one end of said lever-fixing member is further provided in said support side section or the other end of said lever member, and an insertion hole-heating unit disposed in a position adjacent to the insertion hole, for heating the interior of the insertion hole, is further provided, and wherein, when said male coupling body is coupled to the female coupling body, said end section of said support side section is connected to the other end of said lever member by blocking the insertion hole with a thermoplastic material, after one end of said lever-fixing member is inserted in said insertion hole.