Hot working of FeCrAl alloy for nuclear fuel cladding was investigated by thermal simulation compression experiment under deformation temperature of 800~1000 ℃ and strain rate of 0.001~1 s-1. The constitutive equation of the hot deformation behavior of FeCrAl alloy was established through Arrhenius hyperbolic sine function. Based on the dynamic material model, the processing map of FeCrAl alloy was derived for strain of 0.05~0.8. Results show that the flow stress of FeCrAl alloy decreases with the increase of deformation temperature and increases with the increase of strain rate. Both the deformation temperature and strain rate will affect the microstructure evolution. According to the processing map, the instability zone of flow behavior of FeCrAl alloy expands and then stabilizes with the increase of strain, and the optimal hot processing safety areas of the alloy are determined as follows: 1) the strain rate < 0.008 s-1 and the deformation temperature 880~1000 °C (when the strain is approximately 0.1); 2) the strain rate < 0.027 s-1 and the deformation temperature > 950 °C (when the strain is ≥ 0.3).