Rotating stall and surge in centrifugal fan have been of concern due to their detrimental effects on performance and possible damage to turbomachinery.Study on the dynamic properties of flows at rotating stall has proved useful to expand the stall margin.And the pressure time series which is obtained at fan rotating stall contain the dynamic properties of rotating stall.Phase space reconstruction is the first step to analyze a nonlinear dynamical system and it can reveal the dynamic properties of the nonlinear dynamical system.In this paper,based on phase space reconstruction theory in nonlinear dynamics,a method is proposed to analyze the dynamics of rotating stall in the fan impeller.The rotating stall of G4-73 type fan is numerically simulated,and the time series of pressure at rotating stall are obtained at various locations at impeller outlet.The technique of phase space reconstruction is applied to these pressure time series,and a low-dimensional dynamical system,which the dynamic properties are included in,is reconstructed.C-C method is used to deal with pressure time series before and after rotating stall,in order to obtain time delay and the embedding dimension of phase space reconstruction.In the reconstruction of phase space,a potential approach is applied to predict the rotating stall for centrifugal fan.The phase space reconstruction is an effective way to capture the dynamical characteristics of rotating stall in advance,and can be applied to the identification of rotating stall accurately.