Subjective voice qualities are difficult to transform into permanent objective visual patterns. Voice spectrography is not a new method of voice analysis. However, in spite of many contributions to the literature, few otolaryngologists have used this interesting method as a clinical tool for evaluating the voice before and after surgical voice procedures. We used the Yanagihara method for classifying degrees of hoarseness, witch is based on the appearance of noise components and loss of harmonic components as the major acoustic factors related to hoarseness. This classification is clinically useful because the severity of hoarseness can be numerically expressed. Changes in the harmonic components were analyzed by voice spectrographic analysis.