Two methods were developed for the determination of intact enrofloxacin (ER) and flumequine (FQ) in presence of their degradation products. In the first method, ER and FQ were determined using first derivative ratio spectrophotometric technique (1DD) at 290 nm and 260 nm in the ranges of 1-12 μg ml-1 and 2-14 μg ml-1, respectively. The second method depends on the quantitative densitometric evaluation of thin-layer chromatograms of both drugs. Good linearities were obtained in the range of 1.5-4 μg ml-1 and 4-14 μg ml-1 for ER and FQ respectively. The proposed procedures retained their accuracy in the presence of up to 70% degradation products for the two drugs. The results obtained by applying the proposed methods were statistically analyzed and compared with those obtained by reported methods.