A drum type washing machine and controlling method thereof is provided. In the drum type washing machine, a tub is provided, a drum is installed in the tub to rotate about a horizontal axis, a driving motor rotates the drum, a key input unit receives a washing instruction from a user, a memory stores a reference quantity value and a reference eccentricity value, a microcomputer controls washing and rinsing operations in accordance with a procedure set by the user upon an input of a start command through the key input unit and it also controls a preliminary spin drying operation to be selectively performed based on a comparison result obtained by comparing a measured laundry quantity and a measured eccentricity with the reference quantity value and the reference eccentricity value, and a driving control unit controlling the driving motor in accordance with a control signal of the microcomputer.