A simultaneous solid-phase preconcentration and spectrophotometric determination method based on adsorption of rhodamine B (RB) and Brilliant Blue FCF (BB) synthetic dyes onto Chromosorb 108 resin was developed. Solution pH, sample, eluent flow rates and eluent type were optimized. RB and BB concentrations were determined at 556 and 630 nm, respectively. Matrix effects of interference components were examined. Preconcentration factors and detection limits of the dyes were calculated. Adsorption isotherms of method, surface micrographs and pH(zpc) of resin experiments were performed. Limit of detections of the method were determined 0.22 and 0.31 mu g L-1 for RB and BB, respectively. The method was successfully applied to determine RB and BB in industrial, foodstuff, cosmetics and environmental water samples. RB contents were found between 2.11 and 5.89 mu g mL(-1) for liquid samples and 17.55 and 370 mu g g(-1) for solid samples. BB concentrations in investigated solid samples were between 3.00 and 53.38 mu g g(-1). BB contents of liquid samples were determined between 1.57 and 9.66 mu g mL(-1). In order to test applicability of the method, analyte addition/recovery technique was also used. Quantitative recovery values ranging from 95 to 103% were obtained from the analyte addition/recovery tests.