15-Deoxy-Δ(12), 14-prostaglandin J2 (15d-PGJ2), a well known peroxisome proliferator activated receptor (PPAR) γ ligand, has been shown to inhibit cellular proliferation and induce apoptosis and differentiation. However, whether 15d-PGJ2 influences the cytokines in the culture supernatant of bone marrow mesenchymal stem cells (BM-MSC) is unknown. This study was purposed to investigate the influence of 15d-PGJ2 on cytokines in the culture supernatant of BM-MSC. The fibroblast-like cells attached to the culture dish from bone marrow of healthy donors were isolated. The immunophenotype and differentiation potential of the obtained cells were detected by flow cytometry and oil red O and von kassa staining respectively to confirm that these cells were BM-MSC. Thereafter, the BM-MSC were cultured with complete medium supplemented with 10, 20, 40 and 60 µmol/L 15d-PGJ2 for 24 hours respectively. The real-time PCR was used to assay the PPARγ mRNA level, the confocal immuno fluorescence technique was used to detect the expression level of PPARγ. The results showed that the BM-MSC underwent apoptosis and got detached from the culture dish when the concentration of 15d-PGJ2 was no less than 20 µmol/L. The PPARγ mRNA level of BM-MSCs cultured with medium containing 10 µmol/L 15d-PGJ2 was higher than that cultured without 15d-PGJ2, and the difference was statistically significant (P < 0.05). The enhancement of PPARγ expression was observed after stimulated by 15d-PGJ2. The protein chip detecting the culture supernatants of BM-MSC cultured with 10 µmol/L 15d-PGJ2 or without 15d-PGJ2 for 24 hours demonstrated that expression levels of some of the cytokines varied. It is concluded that the down-regulation of TIMP-2 exists after treatment of 15d-PGJ2, which is statistical significant.