Objective To determine the rules of acupoints and meridians selection for dysmenorrhea based on data mining.Methods The literature on acupuncture treatment of dysmenorrhea was reviewed and a database of dysmenorrhea prescriptions regarding the main points of acupuncture was established with Excel 2003 software

using the relevance rule and cluster analysis methods in data mining technology to analyze the characteristics and laws in acupuncture prescription.Results One hundred and fourteen acupuncture prescriptions were included.The highest frequency of acupoint

meridian and location was Sanyinjiao(SP 6)

Spleen Meridian

lower limb knee and below knee

respectively.The results of relevance rule indicated that the highest confidence for acupoint combination was SP 6-Taichong(LR 3)

the highest support for acupoint combination was SP 6-Guanyuan(CV 4)

and the results of cluster analysis showed that there were three effective cluster groups.Conclusion The combination of SP 6-LR 3-CV 4 can be applied in the clinic to cure dysmenorrhea

and Zusanli(ST 36)

Ciliao(BL 32)

Zhongji(CV 3)can be matched based on syndrome differentiation.