Objective:To discuss the mechanism of Gutongling Decoction in the treatment of pain due to bone metastasis based on the regulation of MAPK signaling pathway. MethodsThe mouse model of bone metastasis was established,and 40 mice were randomly divided into the sham operation group, model group, Chinese medicine group and control group. Except the sham operation group, the mouse model of bone metastasis was established in the other groups. From 7th day of modeling, the Chinese medicine group was treated with Gutongling Decoction and the control group was treated with tramadol. The mechanical pain threshold was detected by VonFrey fiber to evaluate the analgesic efficacy. The pathology of liver, kidney and heart were observed to evaluate the drug safety. The protein expressions of p-JNK, p-p38 and p-ERK in MAPK signaling pathway in spinal cord were detected by Western blot.  Results:①On the 14th day after modeling, compared with the model group, the mechanical pain threshold was increased in both control group and Chinese medicine group (P<0.05). On the 21st day after modeling, compared with the model group and control group, the mechanical pain threshold was increased in the Chinese medicine group (P<0.05). ②There were no significant changes on the pathology of liver, kidney and heart. ③Compared with the sham operation group, the expressions of p-JNK, p-p38 and p-ERK in spinal cord were increased in the model group (P<0.05). Compared with the model group, the expressions of p-JNK, p-p38 and p-ERK were significantly decreased in the control group and Chinese medicine group (P<0.05). There were no significant differences on the expressions of p-JNK, p-p38 and p-ERK between the Chinese medicine group and control group (P>0.05).  Conclusion:Gutongling Decoction shows good efficacy in the treatment of pain due to bone metastasis, with no obvious adverse effects on heart, liver and kidney. Its analgesic mechanism is related to regulating the protein expressions of p-JNK, p-p38, p-ERK in MAPK signaling pathway.