A coaxial connector with a built-in capacitor includes: a core wire connection terminal having, on a rear end thereof, a core wire connection portion for connecting thereto a core wire of a coaxial cable; an inner terminal having, on a tip end thereof, a fitted/connected portion fitted and connected to an other party's terminal; an insulator holding the inner terminal while covering an outer circumference of the inner terminal, and having a holding hole of the core wire connection terminal on a rear end thereof; a shield terminal having, on a tip end thereof, a cylindrical shell portion that covers an outer circumference of the insulator, and having, on a rear end thereof, a shield conductor crimping portion for crimping and connecting thereto a shield conductor of the coaxial cable; and an inner dielectric that is sandwiched between a tip end portion of the core wire connection terminal and a rear end portion of the inner terminal, and thereby composes a capacitor function portion while using, as opposite electrodes, the tip end portion of the core wire connection terminal and the rear end portion of the inner terminal.