Titanium-6242 $({alpha}+{eta})$ alloy has been used for aircraft engine components such as disks and blades, because it has an excellent strength/weight ratio at high temperatures. When this material is forged to manufacture disks, process parameters should be carefully designed to control strain and temperature distributions within the process windows by which desirable mechanical properties can be produced. In the present investigation, it was intended to design the process parameters for a conventional hot forging of this material by using a rigid-thermoviscoplastic finite element analysis technique. It was assumed that the process was performed by a screw press which is capable of maintaining a constant ram speed during loading. From the analysis results, it was found out that the initial temperature of the workpiece and the die shape were important parameters to control the forging process. In result, these parameters were properly designed for hot forging of a disk with specific dimensions.