The investigation was carried out to study the effect of wet heat setting and subsequent dry heat setting on the physical properties of regular acrylic fiber (Fw type) and conjugate acrylic fiber (Gw type). The physical properties of fiber such as tenacity, elongation, and dyeability are found to be affected in proportion to the increased degree of shrinkage at temperat ure below 13$0^{circ}C$ by wet heat setting. Yellowing is observed at the same degree on the dry heat treated Fw and Gw type. But there is a significant difference in the degree of yellowing of two types of acrylic fibers setted by dry heat at the temperature above 18$0^{circ}C$. The change is physical properties of Gw type is greater than of Fw type on alkaline solution treatment. The change of physical properties by boiling water treatment is more profound with Gw type than Fw type. The stress relaxation of Gw and Fw type is significantly affected by increasing the temperature of heat treatment.