Abstract: According to the FAO/WHO rules about the amino acid composition standard mode, the optimal amino acid complementary ratio of oat and chickpea was determined as 138:18（ m/m）. The formula of oat-chickpea compound beverage were optimized by single-factor and orthogonal experiments, the stability of the beverage was optimized by response surface test. The results showed that the optimal formula of the compound beverage was as follows: the ratio of material to liquid（oat chickpea compound powder : water） 1 ∶16（g/mL）, white sugar adding amount 20 g/L, and citric acid adding amount 2 g/L. The compound beverage prepared with the above formula had the best taste, with a sensory score of 88.63 ±0.97. The best stabilizer formula of the compound beverage were: sodium carboxymethyl cellulose 0.8 g/L, xanthan gum 0.5 g/L, and sodium alginate 0.3 g/L. Under these conditions, the composite drink had the highest stability, with a centrifugal sedimentation rate of 12.40% ±0.07%.The results provide theoretical support for the processing of compound beverage of cereals and beans.