A combined application of the fractional wavelet transform-continuous wavelet transform to the quantitative resolution of the overlapping signals of olmesartan modoxomil and hydrochlorothiazide in a binary mixture was presented. In this work the recorded absorption signals of two compounds in the range 4-12 μg/mL olmesartan and 2-10 μg/mL hydrochlorothiazide were processed by the fractional transform approach and with the continuous wavelet transform, respectively. The proposed combined complex signal analysis method was validated by analyzing the synthetic binary mixtures of the related compound. By analyzing the statistical parameters we conclude that the new approach is suitable to be used for the quality control of the commercial samples of compounds. © 2011.