A bionic digestion determination method for the total quantity of digestible carbohydrates of feed includes the following steps that 1, sample preparation is carried out; 2, a buffer solution and simulated digestive juice of the stomach and the small intestine and other reagents are prepared; 3, a monogastric animal bionic digestive system is preheated; 4, sample loading is carried out; 5, stomach simulated digestion treatment is carried out; 6, small intestine simulated digestion treatment is carried out, wherein small intestine simulated digestion parameters are set through monogastric animal bionic digestive system control software, and small intestine simulated digestion treatment is started; 7, digestion residue treatment is carried out; 8, the content of reducing sugar in a control sample and the content of reducing sugar in an analysis sample are determined with the DNS colorimetric method, and the total quantity of digestible carbohydrates of the feed is worked out. According to the bionic digestion determination method for the total quantity of digestible carbohydrates of the feed, the external digestion process is automatically controlled in the monogastric animal bionic digestive system, and the test result is high in reproducibility and precision; the workload of operators is reduced, system errors caused by manual operation are eliminated, and the detection efficiency is high.