Romifidine (ROMI), an α2 – adrenergic agonist has been used in different animal species, but its clinical use for donkey surgery is not well documented. The purpose of this study was to evaluate clinically the sedative, analgesic and biochemical effects of ROMI in donkeys undergoing surgical operation. Ten clinically healthy donkeys weighing between 150 and 250 kgs, and aging between 4 and 7 years old were used in this investigation. The recommended dose was 80 µg/kg of romifidine HCl, diluted in 4 ml saline and administered intravenously in donkeys undergoing castration prior animal preparation for aseptic surgery. Sedative, analgesic and clinico-biochemical effects were recorded at 0 (base value) and 15, 45, 75 and 120 min. post ROMI injection. Sedation was determined by the changes in animal behavior after drug administration. Onset and duration of analgesia was assessed using pin pricking. Respiratory rate (RR), rectal temperature (RT) and pulse rate (PR) were also recorded. Blood samples were collected at the same intervals for hemato-biochemical analysis. Descriptive statistical analysis was performed. Sedation was proved in all donkeys characterized by drooping in head and neck, relaxation of lower lip with great reduction of eye alertness within two minutes and lasted for 86.33 ± 0.88 min. It was enough to handle and prepare the animal for aseptic castration. Analgesia with ROMI occurred at 2.0 ± 0.54 min. and persisted for 68.33 ± 4.40 min. Slight ataxia was observed in three donkeys during standing, characterized by reduction in co-ordination. Salivation and urination were recorded. No significant changes were revealed in clinical or hemato-biochemical findings except significant decrease in creatinine and significant hyperglycemia during the period of the experiment. It was concluded that ROMI (80 µg/kg) proved as an effective sedative and analgesic and used safely for undertaking elective surgery in donkeys.