Abstract: This work shows an approach based on Chaari Complex Mother Wavelet for the evaluation of harmonic content of power system waveforms. This paper is based on the work developed by Pham and Wong  and it is an improvement of the algorithm that they made. Their algorithm can simultaneously identify all harmonics including integer, noninteger and subharmonics based on Gaussian Wavelet. In this work the Wavelet Continuous Transform is applied via a sum based on a modification of the Chaari Wavelet to get harmonic content of a signal. If this modification is used in the calculus of Pham and Wong  then better results can be obtained in the determination of harmonic content. Key–Words: Harmonic, Wavelet Continuous Transform, Power System Waveforms.