Normal 0 false false false MicrosoftInternetExplorer4 /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Table Normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-parent:""; mso-padding-alt:0in 5.4pt 0in 5.4pt; mso-para-margin:0in; mso-para-margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:10.0pt; font-family:"Times New Roman"; mso-ansi-language:#0400; mso-fareast-language:#0400; mso-bidi-language:#0400;} In the present study, we investigated the ultrasonically assisted extraction(UAE) and high-performance liquid chromatography (HPLC) determination of chondroitin sulfate(CS) from fish heads. Firstly, the optimized parameters for CS extraction were obtained by using Box–Behnken design(BBD) and response surface methodology(RSM) based on the single-factor experiments. As results, the optimum conditions were ultrasonic time 45min, ultrasonic power 280W and solvent/material ratio 6ml/g. Under these conditions, the experimental yield of CS was 4.623%. Secondly, the CS was purified by DEAE-Cellulose 52 chromatography and Sephadex G-100 chromatography to afford purified CS. Finally, we developed a simple method for the determination of glucuronic acid (GlcA) and N-acetylgalactosamine (GalNAc) in purified CS by HPLC with a diode array detector (DAD). The results showed that there were obvious saccharides peaks in CS.