A fluorometric method, based on the fluorescence properties of the aluminium(III)-hesperidin complex, for the determination of hesperidin in human plasma and pharmaceutical forms has been developed and validated. The complex shows a strong emission in the presence of the surfactant betain sulphonate SB 12 at 476 nm with excitation at 390 nm. The linearity range for pharmaceutical forms of hesperidin was 0.06-24.4 μg mL -1 with a limit of detection, LOD, of 0.016 μg mL -1 and a limit of quantification, LOQ, of 0.049 μg mL -1 . Recovery values in the range 99.3-99.7 % indicate good accuracy of the method. A linear dependence of the intensity of fluorescence of the complex on the concentration of hesperidin in plasma was obtained in concentration range from 0.1-12.2 μg mL -1 . The LOD was 0.032 μg mL -1 while LOQ was 0.096 μg mL -1 . Recovery values were in the range 98.4-99.8 %. The reliability of the method was checked by an LC-MS/MS method for plasma samples and an HPLC/UV method for tablets with direct determination of hesperidin after separation. Linearity range in determination of hesperidin in pharmaceutical forms was obtained in the range from 0.05 to 10.00 μg mL -1 . The LOD was 0.01 μg mL -1 and the LOQ was 0.03 μg mL -1 . The linearity range for the determination of hesperidin in plasma was 0.02-10.00 μg mL -1 with an LOD 0.005 μg mL -1 and an LOQ of 0.015 μg mL -1 . The good agreement between the two methods indicates the usability of the proposed fluorometric method for the simple, precise and accurate determination of hesperidin in clinical and quality control laboratories.