Objective:To study Chen Yiping’s medication rules in the treatment of idiopathic membranous nephropathy (IMN) based on data mining. MethodsThe information and prescriptions of outpatient cases with IMN treated by Chen Yiping were collected and analyzed by complex network toolbox. The relevance was evaluated by mutual information method based on information entropy, and the significant threshold of correlation degree was automatically determined by random permutation test. Based on those above, the complex network was established to measure the importance of relationship between drugs through support and confidence degree, and explore the core couplet medicines through association rules.  Results:①218 cases informations were collected, and 613 prescriptions were extracted, which including 198 medicines, and the accumulated usage frequency was 10 140 times. ②There were 21 medicines with usage frequency more than 60 times, including Baizhu (Atractylodis Macrocephalae Rhizoma), Huangqi (Astragali Radix), Danggui (Angelicae Sinensis Radix), Cangzhu (Atractylodis Rhizoma ), Shanyao (Dioscoreae Rhizoma), Fuling (Poria), Zhuling (Polyporus), BaihuaSheshecao (Hedyotis Herba), Jiangcan (Batryticatus Bombyx), Yiyiren (Coicis Semen), Danshen (Salviae Miltiorrhizae Radix et Rhizoma), Dangshen (Codonopsis Radix), Banzhilian (Scutellariae Barbatae Herba), Furongye (Hibisci Mutabilis Folium), Jinying (Rosae Laevigatae Fructus), Gouji (Cibotii Rhizoma), Yinyanghuo (Epimedii Folium), Tusizi (Cuscutae Semen), Gegen (Puerariae Lobatae Radix), Chuanxiong (Chuanxiong Rhizoma) and Chonglou (Paridis Rhizoma), which can be taken as the basic drugs in Professor Chen Yiping’s treatment on IMN. Among these drugs, the usage frequency of Baizhu, Huangqi, Danggui, Cangzhu, Shanyao and Fuling was over 90%, which can be considered as core medicines. ③The usage frequency of qi-supplementing medicines, heat-clearing medicines, medicines for diuresis and diffusing dampness, medicines for activating blood and removing blood stasis and dampness resolving medicines was higher. ④According to the association rules analysis, 627 couplet medicines were achieved, and 24 of them were considered as core couplet medicines with AVCH>1. Meanwhile, 4 basic prescriptions were achieved by BK algorithm.  Conclusion:Professor Chen Yiping’s treatments for IMN focus on spleen deficiency and dampness-heat and blood stasis blocking vessels and meridians, and the therapies of benefiting qi and clearing heat, inducing diuresis and eliminating dampness, promoting blood circulation for removing blood stasis are applied. The core medicines are Baizhu, Huangqi, Danggui, Cangzhu, Shanyao and Fuling, 24 core couplet medicines and 4 basic prescriptions are made.