Abstract: Taking the lost foam shell cast coating as the research subject, the influence of mixing time and standing time on the viscosity and rheological properties of the coating was investigated. The results show that the viscosity of the coating first decreases with the increase of the mixing time and then reaches to a stable value. The viscosity of the coating first increases and then decreases with the increase of the standing time. To garantee the service performance of the coating, the mixing time should no lower than 50 min and the standing time should no bigger than 40 h.