The hot deformation behavior of an as-cast OCrl7Mnl4Mo2N duplex stainless steel has been studied by hot compression test at the temperature range from 1000℃ to 1200℃, and the strain rates are 0.1 s-1, 1 s-1 and 5 s-1, respectively. It was found that during hot deformation there is only dynamic recovery taking place within the δ-ferrite phase, but the γ-austenite phase undergoes dynamic recrystallization. The activation energy of the steel for hot compression is estimated to be 480 kJ/mol. The hot deformation behavior of an as-cast OCrl7Mnl4Mo2N duplex stainless steel has been studied by hot compression test at the temperature range from 1000 ° C to 1200 ° C, and the strain rates are 0.1 s-1, 1 s-1 and 5 s-1 , respectively. It was found that during hot deformation there is only dynamic recovery taking place within the δ-ferrite phase, but the γ-austenite phase undergoes dynamic recrystallization. The activation energy of the steel for hot compression is estimated to be 480 kJ / mol.