Quinizarin (Qz) is 1,4-dihydroxy-9,10-anthraquinone, exhibiting important potential applications in medicine. However, this molecule typically exhibits low water solubility at room temperature. Recently, the supramolecular host–guest interactions have been the subject of very active research due to their wide spread applications in various areas like pharmaceuticals, sensors, etc. Cyclodextrins (CDs) have been the most extensively investigated due to their higher solubility in aqueous medium. This work proposes the use of β-cyclodextrin (β-CD) to increase the Qz´s solubility through a study carried out via cyclic voltammetry recorded over a carbon paste electrode (CPE) vs Ag/AgCl: the potential sweep started at −0.1 V in the anodic direction at 0.1 Vs⁻¹ rate. The switching potential was recorded in −0.980 V at pH 12.794, in the CPE/66 µM Qz system. Quinizarin (Qz) cyclic voltammetry presented a sharp reduction peak at −0.756 V, with increasing β-CD concentration that evidences the formation of second reduction peak in such a way that the Qz now presents two sharp reduction peaks at −0.895 V and −0.683 V. The formation of a second reduction peak and the potential shift to more positive values is indicative of the of formation of the quinizarin-β cyclodextrin complex in aqueous solution.