This study focused on anaesthesia and cardiopulmonary effects of tiletamine-zolazepam/xylazine/tramadol in miniature pigs and its effects on endothelium-derived vasoactive factors. A total of 14 eight-month-old Chinese experimental miniature pigs were used in this study. Tiletamine-zolazepam (3.5 mg·kg^-1), xylazine (1.32 mg·kg^-1) and tramadol (1.8 mg·kg^-1) were administered i.m.; blood pressure and heart rate were recorded. At the same time, blood was collected through precaval vein, and nitric oxide, endothelin, 6-keto-PGF_1α and thromboxanes B₂ were determined by colorimetry and radioimmunoassay. The mean times to dorsal recumbency, duration of immobilization, standing and walking were 2.26 ± 0.72, 87.57 ± 9.61, 25.63 ± 12.55 and 36.70 ± 14.53 min, respectively. Blood pressure was significantly changed at 10 and 80 min (P < 0.01), and the heart rate ranged from 89 to 134 bpm without episodes of severe bradycardia or tachycardia. Significantly positive correlation was observed between endothelin, thromboxanes B₂ and blood pressure as well as the heart rate (P < 0.05). There was negative correlation between PGI₂ and blood pressure as well as heart rate (P < 0.05). The results showed that endothelin, 6-keto-PGF_1α and thromboxanes B₂ participated in the changing of cardiopulmonary parameters which were caused by tiletamine-zolazepam-xylazine-tramadol anaesthesia in miniature pigs, and the 6-keto-PGF_1α, ET and TXB₂ concentrations in plasma participated in the changing of blood pressures during anaesthesia. Therefore, we can recommend tiletamine-zolazepam/xylazine/tramadol for anaesthesia in pigs, and this study also contributes to the evaluation of the effect of endothelium-derived vasoactive factors during anaesthesia.