In this paper, fixed bed regime and spouting bed regime are observed successively with the increase of superficial gas velocity for Geldart-A powder in a conical bed with three cone angles. The characteristics of the regime for Geldart-A powder differ from that for the Geldart-D powder due to the disappearance of partially fluidized bed regime. The conditions of the regime transition and the hydrodynamics for two flow regimes have been studied in detail.