The utility model relates to an improved handle driving portion of a handle type lock with a replaceable lock core, which comprises am outer casing, an inner casing, a sleeve ring, a rotary shaft and the lock core. A positioning part is arranged on the inner circumferential face of the rotary shaft; a plurality of protruded clamping blocks are arranged on one end; a fixed part which is in concave and convex fitting with the positioning part is arranged on the position of the sleeve ring, and the position corresponds to the positioning part on the rotary shaft. The sleeve ring is arranged in the rotary shaft; the fixed part and the positioning part are under a clamping state and form stable positioning in an axial direction and a radial direction. An 8-shaped hole of the outer casing is extended inwards, and then an 8-shaped clamping edge is formed; the clamping edge is clamped and positioned in the 8-shaped hole of the inner casing after the inner casing and the rotary shaft are assembled; the 8-shaped holes of the inner casing and the outer casing keep a state of contraposition permanently, and have the safe effect of reinforcement.