In this study, lactic acid bacteria (LAB), Weissella cibaria and Kluyveromyces marxianus were mixed and fermented. The symbiosis of the two strains was studied by measuring strain growth curve. Compared the baking and flavor characteristics between mixed bacteria fermentation (MBF) and single bacteria fermentation of whole wheat bread by analyzing cellulase activity and production of exopolysaccharide (EPS). Results: Compared with the cell counts of single bacteria fermentation [LAB: 9.51 lg (CFU/g), yeast: 8.21 lg (CFU/g)], the cell counts of LAB and yeast in the MBF reached 9.61 and 8.09 lg (CFU/g), respectively, indicating that the two strains had a good symbiotic relationship. Compared with the single LAB fermentation, cellulase activity in the MBF with K. marxianus increased, and the extracellular β-glucosidase activity was 13.59 U/g, increased by 128.40%. After 24 h fermentation, water extractable arabinoxylan (WEAX) content in the sample increased from 0.77 g/100 g to 1.89 g/100 g. In addition, the MBF had the highest EPS content produced of 7.54 g/kg. Compared with whole wheat bread without sourdough, the specific volume and elasticity of the bread containing MBF significantly improved (P＜0.05), as bread crumb hardness decreased. The results of flavor characteristics showed that the flavor intensity of bread containing MBF was significantly higher than that of bread containing samples from single LAB fermentation. In addition, the whole wheat bread had a richer wine and fruity flavor. Sensory evaluation confirmed that whole wheat bread with MBF had the highest overall acceptance compared to other groups.