The invention relates to a human body gastrointestinal tract bionic system and a simulation experiment method based on the system. The system comprises a system controller, an intestinal flora planting system, a simulation digestion system, a simulation absorption system, a stirring system, a rate control system, a gas path system, a temperature adjusting system, a pH adjusting system, a digestion liquid reagent bottle, an absorbing liquid reagent bottle and a collector. The method comprises the following steps: setting parameters of the control system, preparing planting colloidal particles, planting the intestinal flora, simulating digestion and the like. The system simulates gastrointestinal tract digestion, absorption and intestinal microecology of human bodies under in-vitro conditions, is real in simulation and good in reproducibility, and us applicable to study on the fields of nutriology, toxicology, physiology, microbiology and the like as intelligent control is adopted.