A bat swing training machine for improving a user's bat swing technique and developing muscular strength includes a frame carried by an adjustable post for height adjustment and two mounting brackets for installation in various locations. The machine also includes a torsion spring, a swing arm with swivel linkage and a bat handle. The machine provides torsional resistance with precise positional control throughout the swing motion and does so equally for right and left handed swings. Backswing is relatively un-resisted thereby allowing the athlete or trainee to stay in position and continuously repeat the swing motion.