Since the ¹³C NMR spectroscopic method was introduced to determine the isoelectric point of amino acid, more amino acids has been studied for the isoelectric point. Anasazi EFT 60 MHz FT-NMR Spectrometer has been particularly used to perform the project without deuterated solvent. The isoelectric points of amino acids determined by ¹³C NMR spectroscopic method have been compared with the corresponding literature values. Further application of the spectroscopic method will be discussed.