Glucocorticoids (GCs) are hormones with anti-inflammatory and immuno-suppressive effects. The use of hormonal medicine like GCs may cause systemic adverse effects. In the present study, the cellular response of murine pre-osteoclast cell line RAW264.7 to dexamethasone (DEX) was investigated and the result demonstrated that DEX may stimulate RAW264.7 cells proliferation. Changes in gene expression involved in RAW264.7 cells proliferation stimulated by dexamethasone were investigated using cDNA microarrays containing 1000 cDNAs. It was found that 67 genes were regulated by DEX and could be grouped into 8 functional categories, including cell cycle regulation, cell survival, metabolism, pro-inflammatory effect, cytoskeleton, proteasome, signaling transduction and transcription factors. Moreover, some signaling pathways that involve in modulation of DEX on RAW264.7 cells functions were identified, including p53, 14-3-3 gamma, MAPK, Elk-1, I kappa B and Ifn related pathways.