Objective This study was undertaken to determine the effect of Whallak-tang on expression of CD/ cytokine Genes. Methods The expression of CD/ Cytokine Genes were examined by cDNA microarray using the human mast cell line(HMC-l). Results The expression of ATP5F1, FLJ20671, unknown, KIAA0342, OAS2, unknown genes were increased in 200 similar to 300% range. The expression of unknown, MDS006, IFITM1, MRPL3, ZNF207, FTH1, FBP1, NRGN, NR1H2, KIAA0747 genes were decreased in 0 similar to 33% range. Conclusion These results would provide important basic data on the possibility of the clinical treatment of Whallaktang in musculoskeletal disease.