The correlation of fluidity between solid-liquid and solid gas suspensions was examineed using the thixotropy model proposed by Usui et al., (2000a, 2000b, 2001) Shear-thinning behavior was observed for a solid-gas suspension of calcium carbonate particles. The decrease in apparent viscosity of the solid-gas suspension is attributed to the breakdown of agglomerative structure with the increase in shear rate. It was found that the predicted inter particle bonding energy for the solid-gas suspension corresponded well to that obtained for a solid-liquid suspension. The same tendency was reported previously for the case of silica suspension. Since the suspension viscosity is not greating sensitive the change in inter particle bonding energy, it may be possible to predict solid-gas suspension viscosity by predicting the inter particle bonding energy for a solid-liquid suspension, and by using the thixotropy model proposed by the present authors.