Abstract： Objective： To study the administration rule of Prof. LIU Aimin in treating eczema according to syndrome differentiation based on data mining technology. Methods：Data mining was performed on 130 cases with eczema，including 298 prescriptions， cured by Prof. LIU in outpatient department by TCM Inheritance Assistant System V2.5， and the frequency of Chinese herbs，herbal combinations，the natures，flavors and channel entry of herbs as well as the correlation of herbs were obtained. Results：Data mining results showed that Prof. LIU's administration rules in treating eczema were as follows. ①In terms of natures， the main herbs were warm and cold， and the frequency ratio of them was 1.28∶ 1. ②In terms of flavors，the main herbs were bitter，bitter and sweet，accounting for 98.6%，and the ratio of the flavors was close to 1∶ 1∶ 1. ③In terms of channel entry， the herbs entered the channels of lung， spleen， stomach and bladder. ④The number of herbs in the prescriptions was usually around 12，and the prescriptions were succinct. Herbs with a frequency of more than 90 were Cortex Phellodendri Chinensis，Cortex Dictamni，Radix Saposhnikoviae，Rhizoma Atractylodis，Semen Coicis， Pericarpium Citri Reticulatae， Radix Bupleuri， Radix et Rhizoma Glycyrrhizae， Herba Ephedrae， Radix Astragali， Poria，Semen Phaseoli，Ramulus Cinnamomi. The common herbal combinations were：①Cortex Phellodendri Chinensis and Cortex Dictamni， ② Cortex Phellodendri Chinensis and Semen Coicis， ③ Cortex Phellodendri Chinensis and Rhizoma Atractylodis，④Cortex Dictamni and Rhizoma Atractylodis，⑤Cortex Phellodendri Chinensis and Radix Saposhnikoviae. The common herbal pairs were Poria and Radix Angelicae Sinensis，Cortex Magnoliae Officinalis and Rhizoma Zingiberis，Poria and Semen Lablab Album， dry- fried Rhizoma Atractylodis Macrocephalae and Herba Ephedrae， Rhizoma Atractylodis and Radix et Rhizoma Glycyrrhizae. The core herbal combinations were Concha Ostreae- Radix Bupleuri- Radix Astragali，Radix Scutellariae- Radix Cyathulae- Scolopendra， Radix et Rhizoma Glycyrrhizae Praeparata cum Melle- Radix et Rhizoma Glycyrrhizae- Semen Coicis，Herba Schizonepetae- Poria- Radix Saposhnikoviae，Radix Paeoniae Alba- Cortex Phellodendri Chinensis- Rhizoma Zingiberis Recens. The new prescriptions were： ①Concha Ostreae， Radix Bupleuri， Radix Astragali， Fructus Amomi and Semen Lablab Album；②Radix Scutellariae，Radix Cyathulae，Scolopendra，Rhizoma Dioscoreae and Endothelium Corneum Gigeriae Galli； ③ Radix et Rhizoma Glycyrrhizae Praeparata cum Melle， Semen Coicis， Cortex Phellodendri Chinensis and Fructus Jujubae；④Herba Schizonepetae，Poria，Radix Saposhnikoviae，Radix Aconiti Lateralis Praeparata and Herba Ephedrae；⑤Radix Paeoniae Alba，Cortex Phellodendri Chinensis，Rhizoma Zingiberis Recens，Radix et Rhizoma Glycyrrhizae Praeparata cum Melle and Fructus Jujubae. Conclusion： Prof. LIU's administration rule in treating eczema reflects his academic thought of examining dampness and seeking the pathogenesis，as well as attaching importance to the unity of nature and human and syndrome differentiation of zang-fu organs.