OBJECTIVE：To dev elop and apply a parenteral nutrition prescription decision support system for medical institutions and provide theoretical basis for improving clinical parenteral nutrition precision treatment. METHODS ：Based on the review points of parenteral nutrition prescription ，the parenteral nutrition prescription decision support system was designed ；the function points and prescription review logic of each module of the system were discussed ，and the system was also used to review 100 pieces of clinical parenteral nutrition prescriptions. RESULTS ：Information-based parenteral nutrition prescription decision support system included evaluation index management module ，drug management module ，index knowledge management module ， index calculation and evaluation module ，feedback and tracking module. The logic of parenteral nutrition prescription review were based on the evaluation indexes ，and rationality knowledge base ，safety knowledge base and drug attribute base were constructed. Based on the above knowledge bases ，patient information and prescription information call and calculation ，the evaluation result set of safety and rationality of the prescription was finally formed. Based on this design concept ，the parenteral nutrition prescription decision support system realized the automatic review and warning of various indicators in TNA prescription ，and can quickly and efficiently review the safety and rationality of parenteral nutrition prescription. Through manual judgment ，the audit results of 100 prescriptions by the system were all correct. CONCLUSIONS ：The basis of parenteral nutrition prescription review is the formulation of evaluation indexes ，and the technical difficulty lies in considering the individuality and rationality as well as the safety and stability of parenteral nutrition solution at the same time. The application of a well-structured information system will promote the precise and reasonable medication of parenteral nutrition and improve work efficiency of medical personnel.