The invention discloses a molding and using method for a bulk drug gastrointestinal absorption prediction BSPK model, which establishes a series of functions based on the bulk drug dissolution, settlement and absorption in multiple gastrointestinal compartments, and which takes into account many factors and variables as follows: drug logP, logD, pKa, solubility, dissolution rate, density, partical diameter, particle forms, particle diameter distribution, settlement rate, settlement particle diameter, settlement time, permeability and human gastrointestinal physiological conditions, etc. The method is applicable to acidic, alkalic, neutral and acidic-alkalic drug absorption prediction in different gastrointestinal parts. The invention, which is used in active compound gastrointestinal absorption prediction, not only raises the early stage drug screening accuracy, but also reduces the workload of preformulation researches. In this way, medicine clinical application process is accelerated with great scientific research value and application prospect.