A drum type washing machine having - a motor, - a tub inclinedly provided at a predetermined angle against a bottom of the drum type washing machine, - a drum (20, 200) mounted within the tub and inclinedly provided at a corresponding predetermined angle, the drum (20, 200) having a drum center of a cylinder shape and a drum back connected to an opening formed in a side of the drum center to define a rear surface of the drum (20, 200), - a connector mounted in the rear surface of the drum (20, 200), and - a rotation shaft (50, 500) connected to the connector to transmit the rotation force of the motor to the drum (20, 200), - wherein the drum back is formed in a bowl shape to have a drum expanding part expanded toward an outer side of the drum (20, 200) from the opening of the drum center (28, 280), and a portion of the drum back where the connector is mounted is recessed toward the inside of the drum (20, 200) to reduce the distance between the drum center (28, 280) and the connector; and - a lifter (23, 230) provided within the drum (20, 200) wherein the lifter (23, 230) has a triangle shape getting wider from a front portion toward a rear portion is provided within the drum (20, 200), and the lifter (23, 230) comprises further: a ball installing part formed along a center portion of the lifter (23, 230) in a front-and-rear direction, the ball installing part projectedly formed from the lower surface of the lifter (23, 230) to make the width thereof narrower than the lower surface of the lifter (23, 230); a ball rotatably mounted on the ball installing part; and a wash-water-through-hole formed on the ball installing part; characterized in that the lifter (23, 230) comprises further an oblique surface of a S-shape formed in rear of the opposite sides of the ball installing part, the oblique surface connected to an upper surface of the ball installing part from the lower surface of the lifter (23, 230). - a motor, - a tub inclinedly provided at a predetermined angle against a bottom of the drum type washing machine, - a drum (20, 200) mounted within the tub and inclinedly provided at a corresponding predetermined angle, the drum (20, 200) having a drum center of a cylinder shape and a drum back connected to an opening formed in a side of the drum center to define a rear surface of the drum (20, 200), - a connector mounted in the rear surface of the drum (20, 200), and - a rotation shaft (50, 500) connected to the connector to transmit the rotation force of the motor to the drum (20, 200), - wherein the drum back is formed in a bowl shape to have a drum expanding part expanded toward an outer side of the drum (20, 200) from the opening of the drum center (28, 280), and a portion of the drum back where the connector is mounted is recessed toward the inside of the drum (20, 200) to reduce the distance between the drum center (28, 280) and the connector; and - a lifter (23, 230) provided within the drum (20, 200) wherein the lifter (23, 230) has a triangle shape getting wider from a front portion toward a rear portion is provided within the drum (20, 200), and the lifter (23, 230) comprises further: a ball installing part formed along a center portion of the lifter (23, 230) in a front-and-rear direction, the ball installing part projectedly formed from the lower surface of the lifter (23, 230) to make the width thereof narrower than the lower surface of the lifter (23, 230); a ball rotatably mounted on the ball installing part; and a wash-water-through-hole formed on the ball installing part; a ball installing part formed along a center portion of the lifter (23, 230) in a front-and-rear direction, the ball installing part projectedly formed from the lower surface of the lifter (23, 230) to make the width thereof narrower than the lower surface of the lifter (23, 230); a ball rotatably mounted on the ball installing part; and a wash-water-through-hole formed on the ball installing part;