Flurbiprofen axetil is a nonsteroidal anti-inflammatory drug used for analgesia. Its combination with dezocine has previously shown a superior postoperative analgesic effect compared with that of opioids. The present study compared the analgesic effect between dezocine plus flurbiprofen axetil (DFA) and sufentanil in patients with colorectal cancer (CRC) following resection of the tumor. The study was performed as a prospective, observational study. It included 107 patients who were treated using a patient-controlled analgesia (PCA) pump following the resection of CRC. Patients in the DFA group were given a loading dose of 5 mg dezocine and 50 mg flurbiprofen axetil, followed by PCA with a combination comprising 30 mg dezocine, 200 mg flurbiprofen axetil and 8 mg ondansetron. Patients in the control group were treated with sufentanil at a loading dose of 5-10 µg followed by PCA with a combination of 100 µg sufentanil and 8 mg ondansetron. The DFA group reported lower pain numerical rating scale scores at 2 h (2.4±1.2 vs. 2.9±1.2) and 12 h (2.0±1.0 vs. 2.5±1.2) and reduced rates of moderate-to-severe pain at 12 h (6.7 vs. 21.0%) compared with those in the control group. In addition, the number of PCA boluses in the DFA group was lower than that in the control group [median (interquartile range), 6.0 (4.5-8.5) vs. 8.5 (5.0-11.0)]. The total satisfaction rate was increased, albeit not significantly, in the DFA group compared with that in the control group (80.0 vs. 62.9%). The levels of tumor necrosis factor-α at 24 and 48 h, and of interleukin-6 at 24 h were decreased in the DFA group compared with those in the control group. The incidences of adverse events did not differ between the groups. These findings indicate that DFA provides more effective analgesia, improves patient satisfaction and reduces the levels of pro-inflammatory cytokines with similar adverse effects compared with those of sufentanil in patients after CRC resection.