The isothermal constant strain rate compression tests of a Ti3Al based alloy were conducted by THERMECMASTER-Z simulator and the deformation behavior at the temperature of 950-1350 oC and strain rate of 0.001-10 s-1 were investigated. The processing maps under these deformation conditions were constructed and the hot working parameters were then optimized based on the generated processing maps. The processing maps developed on the basis of dynamic material model exhibit following five domains. (1) The alloy exhibits domain of flow localization and adiabatic shear bands in the temperature range of 950-1100 oC and strain rate range of 0.05-10 s-1. (2) The region of flow instability occurs in the temperature range of 1100-1350 oC and strain rate range of 0.1-10 s-1. The manifestation of flow instability is non-uniform deformation of β grains. (3) The alloy undergoes dynamic recovery in the temperature region of 1250-1350oC and a strain rate below 0.01 s-1. The materials exhibit significant grain coarsening in this domain. (4) The subgrain could be found in the temperature range from 1100 oC to 1180 oC and the strain rate from 0.001 to 0.015 s-1 with a power dissipation efficiency above 0.55. (5) The deformation characteristic of the Ti3Al based alloy in the temperature ranger of 970-1010 oC and strain rate range of 0.001-0.01 s-1 is superplasticity with power dissipation efficiency above 0.5. The last two regions can be considered as the optimal parameter range of isothermal compression for Ti3Al based alloy