A structure of an imaging part in an electronic visualized catheter comprising: an object lens system in which light from an observation object region is incident; a solid state imaging element for receiving an outgoing light from the object lens system and photoelectrically converting an image of the observation object region, a flexible printed wiring board comprising a bottom plate portion, and a pair of side wall plate portions (46B, 46C) that are continuous with both sides of the bottom plate portion, the pair of side wall plate portions (46B, 46C) being formed in a shape that is bent with respect to the bottom plate portion so as to extend in the same direction; and a sleeve with a hollow tubular shape in which at least a distal end portion is opened, wherein: at least a lens face of a light outgoing side of the object lens system is formed to be planar, and the lens face of the light outgoing side of the object lens system is joined to a light receiving surface of the solid state imaging element; in the bottom plate portion, an opening portion that penetrates a plate surface of the bottom plate portion is formed; the solid state imaging element is, among the two surfaces of the bottom plate portion of the flexible printed wiring board, arranged on the surface of the side at which the pair of side wall plate portions (46B, 46C) extend, and further the light receiving surface of the solid state imaging element is positioned so as to face the opening portion; the portion of the emission side of the object lens system is arranged within the opening portion; and the object lens system, the solid state imaging element, and the flexible printed wiring board are housed in the sleeve so that the incident side of the object lens system is positioned at the opened distal end portion of the sleeve. an object lens system in which light from an observation object region is incident; a solid state imaging element for receiving an outgoing light from the object lens system and photoelectrically converting an image of the observation object region, a flexible printed wiring board comprising a bottom plate portion, and a pair of side wall plate portions (46B, 46C) that are continuous with both sides of the bottom plate portion, the pair of side wall plate portions (46B, 46C) being formed in a shape that is bent with respect to the bottom plate portion so as to extend in the same direction; and a sleeve with a hollow tubular shape in which at least a distal end portion is opened, wherein: at least a lens face of a light outgoing side of the object lens system is formed to be planar, and the lens face of the light outgoing side of the object lens system is joined to a light receiving surface of the solid state imaging element; in the bottom plate portion, an opening portion that penetrates a plate surface of the bottom plate portion is formed; the solid state imaging element is, among the two surfaces of the bottom plate portion of the flexible printed wiring board, arranged on the surface of the side at which the pair of side wall plate portions (46B, 46C) extend, and further the light receiving surface of the solid state imaging element is positioned so as to face the opening portion; the portion of the emission side of the object lens system is arranged within the opening portion; and the object lens system, the solid state imaging element, and the flexible printed wiring board are housed in the sleeve so that the incident side of the object lens system is positioned at the opened distal end portion of the sleeve. at least a lens face of a light outgoing side of the object lens system is formed to be planar, and the lens face of the light outgoing side of the object lens system is joined to a light receiving surface of the solid state imaging element; in the bottom plate portion, an opening portion that penetrates a plate surface of the bottom plate portion is formed; the solid state imaging element is, among the two surfaces of the bottom plate portion of the flexible printed wiring board, arranged on the surface of the side at which the pair of side wall plate portions (46B, 46C) extend, and further the light receiving surface of the solid state imaging element is positioned so as to face the opening portion; the portion of the emission side of the object lens system is arranged within the opening portion; and the object lens system, the solid state imaging element, and the flexible printed wiring board are housed in the sleeve so that the incident side of the object lens system is positioned at the opened distal end portion of the sleeve.