To develop a draft tube spouted bed (DTSB) for gasification of straw with coal, flow characteristics of the mixture in DTSB before co-gasificating should be studied to get the spouting conditions. The relationship of pressure drop of the bed with superficial air velocity was analyzed, as well as the effects of various parameters such as proportion of mixture, jet diameter and draft tube jet distance (DTJD) on it and the relationship of the circulating rate of the mixture with superficial air velocity. Three regression equations were got by U12(123) uniform design experiments and multiple variable linear regression using SPSS. The dependent in these equations’s was circulating rate of the mixture, pressure drop of unit material height, circulating rate of the mixture of per effective power respectively and the independents were all of proportion of mixture, spout diameter and DTJD. Three equations can be used to forecast hydrodynamic parameters of the mixture in the DTSB.