This study evaluated the relative bioavailability of four brands of ciprofloxacin (500 mg) tablets marketed in Southeast, Nigeria using an in vivo approach. The study was carried out on twelve healthy male rabbits which were given a single dose of ciprofloxacin (500 mg) tablet of the reference (R) and three test (A, B, C) products in the fasting state in a balanced incomplete block design. Serum obtained from collected blood within 24 hours was analysed for ciprofloxacin with microbiology assay while plasma samples were analysed using UV-Vis spectrophotometric analytical method at a wavelength of 272.4 nm. The pharmacokinetic parameters were determined using non-compactmental as implemented in WinNonlin pharmacokinetic program. The 90% confident interval of the log transformed mean values of the test/reference ratios for the pharmacokinetic parameters (Cmax), (AUC0-t), and the (AUC0-âˆÅ¾) were calculated. The pharmacokinetic parameters from the UV-Vis analytical method showed no statistically significant difference between the reference and the tested brands as the mean Cmax obtained for the reference sample (R) was the highest (275.50 (Â ± 3.86) Âµg/ ml) occurring at a tmax of 6.83 (Â ± 1.89) h, followed by B (222.17 (Â ± 2.11) Âµg/ ml) at 5.08 (Â ± 0.98) h, C (202.00 (Â ± 0.55) Âµg/ml) at 3.63 (Â ± 1.02) h and A (192.00 (Â ± 1.10) Âµg/ml) at 7.00 (Â ± 1.11) h. The value obtained for the 90% CI for log-transformed ration for Cmax reflect that it is within the acceptable range of 80% to 125% as it is for AUC0-t and AUC0-âˆÅ¾ also. The four formulations were considered to be bioequivalent as the peak plasma concentration and AUC parameter analysis of variance reflno significant difference between the reference and the tested brands.