To investigate the flow stress characteristics and deformation?mechanism of MoLa Alloy,The isothermal compression tests were performed over the ranges of temperature 800-1150oC and the strain rate range of 0.001-10 s -1.The results show that the flow stress increases or remain stable with the increase of strain .But the flow stress decrease with the increase of strain in which the deformation temperature is 1000-1150 ℃ and the strain rate is 0.001s-1.A PSO-BP neural network has been established to describe the changing rule of flow stress with the strain rate and deformation temperature .The correlation coefficient and average?relative?error of the network have been calculated to be 0.995 and 1.48% respectively.So it is clear that the PSO-BP model has?good?accuracy .The intrinsic hot workability maps have been constructed based on the polar reciprocity model at strains of 0.3,0.6 and 0.92.?Combing microstructure observation ,it has been found that the buckling form in instability area mainly was local plastic deformation,and deformation mechanism in stability region mainly was dynamic recovery.The suitable processing parameters ranges of MoLa alloy could be inferred to be the deformation temperature range of 1100-1150 ℃ and the strain rates range of 0.001- 0.05 s-1.