Abstract: Objective To explore the application effect of dialectical nursing combined with level three ladder analgesic therapy in the treatment of severe cancer pain. Methods From June, 2014 to June, 2016, 102 patients with moderate to severe pain hospitalized in our hospital were selected, including 30 cases of pulmonary cancer, 24 cases of gastric cancer, 26 cases of liver cancer, 16 cases of colorectal cancer, and 6 cases of cervical cancer. According to the random number table method, the patients were divided into observation group and control group, with 51 cases in each group. Patients in the control group received routine nursing and level three ladder analgesic therapy, and the observation group was treated with the combination of dialectic nursing and level three ladder analgesic therapy. After two months of treatment, the pain relief, side effects and nursing satisfaction were observed and compared between the two groups. Results The pain relief rate in the observation group[86.27% (44/51)] was significantly higher than that in control group[26.78% (33/51)], and the difference was statistically significant (χ²=8.513, P=0.004); the adverse reactions incidence of nausea (χ²=9.543, P<0.01), vomiting (χ²=6.095, P<0.05), dizziness (χ²=5.830, P<0.05) and insomnia (χ²=8.947, P<0.01) in the observation group were significantly lower than those in the control group, with statistical significance; nursing satisfaction in the observation group was significantly higher than that in the control group, and the difference was statistically significant (Z=3.509, P<0.001). Conclusion The dialectic nursing combined with level three ladder analgesic therapy can relieve the cancer pain, and reduce the side effects of the drug, which is worthy of promotion.