Abstract: For finding a novel spouted bed scaled up for biomass gasificating with coal, a rotating draft tube spouted bed (RDTSB) was designed. Before gasificating, co-spouting capabilities of mixture of coal with biomass such as straw in the RDTSB needed to be investigated first. The curve of pressure drop of the bed with superficial air velocity is obtained, as well as the effects of parameters such as proportion of mixture, jet diameter, and draft tube jet distance (DTJD) on this curve and the curve of the circulating rate of the mixture with superficial air velocity. Three regression equations are gained by U12(123) uniform design experiments and multiple variable linear regression using SPSS, in which the dependent is circulating rate of the mixture, pressure drop of unit material height and circulating rate of the mixture of unit effective power respectively and the independents are all of proportion of mixture, spout diameter and DTJD. Three equations can be used to forecast co-spouting capabilities of the mixture in RDTSB.