Abstract: A new method was developed for sensitive and selective determination of bright blue FCF and amaranth in soft drinks, wines, sweets, and jellies by UV-visible spectroscopy. Reduced graphene oxide/magnetite composites were used as adsorbents for the magnetic solid-phase extraction of the sided colorants in food samples. Under optimal conditions, a good linear relationship existed between the absorbance value and the concentration of bright blue FCF (amaranth), with a correlation coefficient of 0.9994 (0.9998), linear range of 0.6~60 μg/L (3~250 μg/L), and detection limit of 0.012 μg/L (0.05 μg/L). The spiked recovery rates of the samples were in the range of 92.19%~98.30%. Experimental results indicated that the proposed method was successfully applied to the analysis of bright blue FCF and amaranth in the food samples.