The invention relates to a preparation method of an antibody-drug conjugate (ADC). Specifically, the method realizes solid-phase preparation of antibody drug conjugates mainly by the combination of antibody-based biomolecules and ion exchange carriers through electrostatic interactions. By optimizing the elution conditions, the drug per antibody ratios (DAR) were controlled and the polymer conjugated drugs were isolated to reduce the use of drugs in the coupling reaction and enhance the targeted therapeutic efficacy of ADC drugs. The preparation method has fewer steps, simple operation, program control, and is conducive to industrial scale-up production, simultaneously realizes zero retention of reducing agent and organic solvent in the preparation process, obviously improves the safety of the medicines, and also reduces the production cost.本發明涉及一種抗體藥物偶聯物（antibody-drug conjugate, ADC）的製備方法，具體而言，該方法主要借助於抗體類生物分子與離子交換載體通過靜電相互作用的結合，實現ADC藥物的固相製備。通過洗脫條件的優化控制藥物與抗體的偶聯比（drug per antibody ratios, DAR）和分離聚體偶聯藥物，降低偶聯反應中藥物的使用量和增強ADC藥物的靶向療效性。該製備方法步驟少，操作簡單，可程序化控制，利於工業放大生產，同時實現製備過程中還原劑和有機溶劑的零留存，明顯提高用藥安全性，也降低了生產成本。
