Two UV-spectrophotometric methods were adopted for simultaneous determination of amprolium HCl, ethopabate and sulfaquinoxaline-Na. The two methods are a double divisor ratio derivative method and ratio dual wavelength method. The three cited drugs were determined by the suggested methods in the range of 6.0-50.0 µg mL-1, 2.0-27.0 μg mL-1 and 3.0-25.0 µg mL-1, respectively. The proposed methods were proved to be selective where the mean percentage recoveries of amprolium HCL, ethopabate and sulfaquinoxaline-Na provided by the double divisor ratio derivative method were 99.29 ± 0.84, 100.36 ± 1.21 and 100.61-101.57 ± 0.15-1.75; respectively. The ratio dual wavelength method mean recoveries were in the range of 98.93-100.45%±0.44-1.42, 99.47-100.67%±0.83-1.65 and 99.97-101.71%±0.10-1.15 for the studied drugs; respectively. Both methods were validated following ICH guidelines. Successful application of the methods for analyzing the three drugs in their veterinary dosage forms; Ampoethoquinone powder was conducted. The obtained results were statistically analyzed and found to be in accordance with those given by the reported methods.