As a new severe plastic deformation (SPD) method, equal-channel double angular pressing (ECDAP) is developed based on equal-channel angular pressing (ECAP) to reduce the offset load. The deformation behaviors of commercial sintered pure tungsten (W) during single pass ECDAP were analyzed quantitatively in this paper by means of finite element simulation and experiment investigation. The results show that, compared with ECAP, the local force of the die distributes more homogeneously and the offset load of the punch is improved with the same parameters. Meanwhile, the average effective strain introduced by ECDAP is similar to that of ECAP. Nevertheless, the uniformity of strain distribution is also greatly improved owing to the secondary shear deformation. In addition, grain size decreases to 1.77 μm in the secondary shear deformation zone and the grains are elongated obviously in the angle zone. Hence, the microhardness was enhanced because of the Hall-Petch strengthening and strain strengthening. These results indicate that the ECDAP process is a promising approach for producing ultra-fine grains metallic materials.