Objective To investigate the effect of adenosine triphosphate on the differentiation of BMSCs into chondrocytes and its mechanism. Methods The primary cells of BMSCs from 4-5 weeks old SD rats were cultured to the third generation in vitro. PNPP method was used to detect the effects of ATP with different concentrations(150, 300 and 600μmol/L) and BBG(receptor inhibitor of P2X7) of on alkaline phosphatase expression in BMSCs. The mRNA expression of multiple cartilage markers was detected by semi-quantitative reverse transcription polymerase chain reaction and real time PCR. Results After ATP was added, the expression of alkaline phosphatase in BMSCs was significantly increased(P<0.05).The highest expression of alkaline phosphatase was observed when ATP concentration was 150 and 300 μmol/L(P<0.05).The expression levels of indicators such as SOX6, SOX9 and COL2A1 were increased(P<0.05). After the addition of P2X7 receptor inhibitor, the promotion effect of ATP on alkaline phosphatase decreased(P <0.05), and the expressions of chondrogenic indicators such as SOX6, SOX9 and COL2A1 were also significantly decreased(P <0.05). Conclusion A certain concentration of ATP can promote the differentiation of bone marrow mesenchymal cells into chondrocytes, which may play a role through the mediation of P2X7 receptor.