The invention discloses an electronic lock core with clutch, which comprises a mechanical rotary core, a rotor, a clutch-plate, an electronic rotary core, a rotating disk, and a mounting disk. The rotor is arranged in the mechanical rotary core, the upper part of the rotor is provided with the clutch-plate, and the upper part of the clutch-plate is provided with the electronic rotary core; the central parts of the rotor, the clutch-plate, and the electronic rotary core are provided with through holes; the inside of the electronic rotary core is provided with an electromagnet and an electroniccircuit arrangement, a contact fixing plate is arranged on the rotating disk, and a rotating clutch-plate is arranged in the mounting disk. The invention also discloses an electronic lock system including the electronic lock core, which comprises the electronic lock core, an electronic key, and a lock casing, wherein the electronic key comprises a key rod and a key casing; the key rod is providedwith a rotating guide groove, the inner cavity of the key rod is provided with electronic elastic contacts, and the inside of the key casing is provided with an integrated circuit. The invention is simple in structure, and excellent in pick-proof performance. The key provides the power for the opening of electronic lock core, and the power consumption required by the electronic lock is reduced.