In this review, a variety of techniques, such as HPLC and electrophoresis, are described for the estimation of individual amino acids as well as the simultaneous estimation of multiple amino acids. Pre-column or post-column derivatization may be utilised for amino acid determination using HPLC. In pre-column derivatization, the amino acid is first derivatized into a particular derivative and then analyzed in the column, whereas in post-column derivatization, the amino acid is first passed through the column for the purpose of separation, and then the separated amino acids are derivatized into their such derivatives that can be detected by fluorescence detector. Pre-column derivatization is employed more frequently than its post-column counterpart. A pre-column derivatization HPLC method was developed for the simultaneous determination of 17 types of amino acids in Asparagi Radix prior to and following heating. As a pre-column derivatization reagent, Phenyl isothiocynide[PITC] was utilised. On a C8 column (C8, 250 X 4.6 mm, 5.0 μm) using gradient elution with 0.1 mol/L pH6.5 acetate buffer solution-acetonitrile as mobile phase A and acetonitrile-water as mobile phase B,and methanol mobile phase C the amino acid derivatives were separated.