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Background & aim: In traditional medicine, Passiflora caerulea is used as a pain relieving and neurogenic malaise.‌ The aim of this study was to evaluate the analgesic efficacy of Passiflora caerulea extract in mature male rats. Methods: In this study, 42 adult male rats were divided into 7 groups: control, MEPC (80, 100 and 300 mg/kg, i.p.) Morphine (1mg/kg, i.p.), indomethacin (10mg/kg, i.p.), and naloxone (100 mg/kg, i.p.) were used. In order to evaluate the analgesic effect of the extract, test ratings, tail-flick and formalin were used. The data were analyzed by ANOVA and Tukey test. Results: 80-300 mg doses of the extract showed significant inhibitory effects on the response of chronic phase of formalin test and the ratings test (p <.0.05). Although there was an increase in tail flick extract, but in this case, the effect induced by morphine was lower compared to controls. The analgesic effect doses of 300 mg kg of indomethacin was significantly higher than chronic phase of formalin (p <0.05). Conclusion: The analgesic effect of Passiflora caerulea, especially in the chronic phase of formalin test was observed, this effect may be due to the presence of flavonoids and tannins found in plants, which its analgesic effect has been proven in the past.