The invention discloses an extensible socket bar. The extensible socket bar comprises an electric wire, socket bars, a slider, an expansion plate, clamping grooves, a clamping plate, clamping columns, a connecting rod, a return spring and a spring tube, wherein the socket bars include a first socket bar and a second socket bar; the slider is located at the internal bottom end of the first socket bar and connected with the same by use of an adhesive; the expansion plate is located in the center of the top of the slider and connected with the same in a sliding manner; each clamping groove is formed in the top of the expansion plate and in a plate-like circular shape, and a plurality of clamping grooves are orderly arranged from left to right; the clamping plate is located at the internal bottom end of the second socket bar and connected with the same by use of an adhesive; each clamping column is located at the top of the clamping plate and in a cylindrical shape, and a plurality of clamping columns are orderly arranged from left to right; the return spring penetrates through the connecting rod, and located between the first socket bar and the second socket bar, and the return spring, the first socket bar and the second socket bar are fastened to each other. The extensible socket bar is ingenious in structure, powerful in function, and capable of preventing interference of plugging into the socket bar when electrical appliance plugs are large and avoiding the waste of the socket bar in use.