Many speech pathologists and laryngologists are frequently coming in touch with the patient of the unilateral vocal palsy and have studied the phonatory characteristics with sound spectrogram, and many sound spectrographic parameters have been showed diversely. So authors studied the various acoustic parameters for sustained vowel including pitch pertubation, jitter ratio, mean jitter, fluctuation of the fundamental frequency, relative noise level and the relative level of higher harmonic components. Authors agree that each variabilities of the each pitch period showed the interesting differences between the normal and the patient with palsy, and also the extent of fluctuation of fundamental frequency was a meaningful parameter. But others were not valuable parameters for the acoustic analysis in patient of the unilateral vocal cord paralysis. So authors report the acoustic characteristics in patient of unilateral vocal cord paralysis with a review of literature.