A bipolar electrode probe (100, 102, 104), comprising: a conductive needle having a longitudinal direction (x) and a transverse direction (y) perpendicular to the longitudinal direction (x); an insulation layer covering the conductive needle and having at least a first opening; a conductive sleeve covering the insulation layer and having at least one second opening; and an insulation sleeve covering the conductive sleeve, wherein the insulation sleeve is configured to be movable back and forth along the longitudinal direction (x), wherein a needle end portion of the conductive needle is exposed from distal ends of the insulation layer, the conductive sleeve and the insulation sleeve,wherein when the bipolar electrode probe (100, 102, 104) is applied with power and a voltage is applied between the conductive needle and the conductive sleeve at a rear end of the bipolar electrode probe (100, 102, 104), a longitudinal electric field is formed from a front end of the conductive needle to the conductive sleeve along the longitudinal direction (x), and a transverse electric field (E2, E2') is formed from the conductive needle to the conductive sleeve via the at least one first opening and the at least one second opening along the transverse direction (y); wherein the bipolar electrode probe (100, 102, 104) has: a front ablation region, where the longitudinal electric field is formed, and a rear ablation region, where the transverse electric field (E2, E2') is formed; wherein a tip of the insulation layer is protruding distally from the conductive sleeve; wherein the conductive sleeve is protruding distally from the insulation sleeve; wherein in a region of the transverse electric field (E2, E2'), a longitudinal insulation distance (dx) exists between a front end of the at least one second opening and a front end of the at least one first opening along the longitudinal direction (x); and a transverse insulation distance (dy) exists between an end of the at least one second opening and an end of the at least one first opening on a same side along the transverse direction (y). a conductive needle having a longitudinal direction (x) and a transverse direction (y) perpendicular to the longitudinal direction (x); an insulation layer covering the conductive needle and having at least a first opening; a conductive sleeve covering the insulation layer and having at least one second opening; and an insulation sleeve covering the conductive sleeve, wherein the insulation sleeve is configured to be movable back and forth along the longitudinal direction (x), wherein a needle end portion of the conductive needle is exposed from distal ends of the insulation layer, the conductive sleeve and the insulation sleeve,wherein when the bipolar electrode probe (100, 102, 104) is applied with power and a voltage is applied between the conductive needle and the conductive sleeve at a rear end of the bipolar electrode probe (100, 102, 104), a longitudinal electric field is formed from a front end of the conductive needle to the conductive sleeve along the longitudinal direction (x), and a transverse electric field (E2, E2') is formed from the conductive needle to the conductive sleeve via the at least one first opening and the at least one second opening along the transverse direction (y); wherein the bipolar electrode probe (100, 102, 104) has: a front ablation region, where the longitudinal electric field is formed, and a rear ablation region, where the transverse electric field (E2, E2') is formed; wherein a tip of the insulation layer is protruding distally from the conductive sleeve; wherein the conductive sleeve is protruding distally from the insulation sleeve; wherein in a region of the transverse electric field (E2, E2'), a longitudinal insulation distance (dx) exists between a front end of the at least one second opening and a front end of the at least one first opening along the longitudinal direction (x); and a transverse insulation distance (dy) exists between an end of the at least one second opening and an end of the at least one first opening on a same side along the transverse direction (y).