The separation performance of the newly developed disengager arms（models A，B）in vortex quick separator（VQS）for FCC disengager was tested experimentallyThe results indicated that the performance of model B was better than that of model AAffected by the structure of model B，the dusty airflow can rotate at a higher speed and gain stronger tangential velocity after ejecting from the outlet of disengager armsConsequently，the dusty airflow in model B can get stronger centrifugal force，which led to the improvement of separation efficiency in VQSThe gassolids flow in VQS was numerically simulated on the platform of commercial computational fluid dynamics（CFD）software，Fluent 6.1Numerical calculation showed that in model B，not only the tangential velocity in the outer vortex area was higher，but also the axial velocity in the downwardflow zone was also higher，which also implied that model B had stronger centrifugal force and higher separation efficiencyFurthermore，the grade efficiency of coarse particles can be improved greatly in model BHence，model B was recommended as the optimal disengager arms in industrial application.