In order to make the drugs can cure the tumor precisely, this paper establishes the tumor immune dynamic model through the differential equation of tumor growth and analyzes the persistence of the tumor immune model. Research on dual anticancer drugs and commonly used coupling methods is carried out to complete the synthesis of polyethylene glycol dual anticancer drug couplers and the antitumor activity is analyzed to derive the degree of inhibition of polyethylene glycol dual anticancer drugs on tumor activity. From the four judging criteria, it was concluded that the polyethylene glycol bis-anti-cancer drug has a better curative effect on tumor cells. Evaluation of polyethylene glycol bis-anti-cancer drugs from four aspects: Apoptosis test, relative tumor growth rate, immunofluorescence staining of tumor tissue sections and antibody endocytosis, it can be found that polyethylene glycol bis-anti-cancer drugs play a role in inhibiting the activity of tumors by 20% and the proportion of apoptosis is 97.6%, which effectively hinders the growth of tumor cells and reduces the multiplicity of tumor cells. Therefore, the polyethylene glycol bis-anti-cancer drug constructed according to the tumor immune model can effectively cure tumor cancer with targeting, can precisely find the location of the tumor and has high research significance for real-time tumor killing.