Two long-acting neuroleptics were used to tranquilize nine captive cheetahs (Acinonyx jubatus). Perphenazine enanthate (3.0 mg/kg) and zuclopenthixol acetate (0.6 mg/kg) were each administered to separate groups of three cheetahs in a double blind trial. Both products were administered together to a third group of three animals at the same dosages. Behavioral effect, duration of effect, and possible side effects were observed by a predefined protocol. Under standardized holding conditions, the cheetahs were observed 5 days before drug administration and 14 days after administration. Daily activity was defined and statistically evaluated by a U-test. A significant reduction of activity was observed after administration in all three trials. Zuclopenthixol acetate at 0.6 mg/kg alone and in combination with perphenazine enanthate caused inappetence, ataxia, extra pyramidal reactions, akathisia, and prolapse of the third eyelid. Zuclopenthixol acetate should not be used in cheetahs. Perphenazine enanthate did not cause inappetence, reduced appetite, or any of the previously mentioned side effects when used alone. It produced satisfactory tranquilization and is suitable and safe for cheetahs at 3.0 mg/kg. This dosage should be varied depending on health, age, and temperament of the individual cheetah.