Experiments of continuous and directional solidification of titanium alloy slabs were performed using authors-designed multi-function directional solidification apparatus with rectangular cold crucible. Influences of processing parameters on the surface qualities of the solidified slabs were studied. It is shown that the slab surface qualities can be effectively improved with increasing of the turns in coil and input power, and with decreasing of withdrawal velocity and re latively Iow position of pedestal to the induction coil. The influences of the processing parameters in the descending order are as follows: the turns in coil, input power, withdrawal velocity and the relative position of pedestal. With optimized parameters, quality slabs free from cracks and ripples were obtained. The solidified structure with good surface quality shows directionally solidified structure.