Abstract: SHG was sulfated by chlorosulfonic acid- pyridine method, and six samples which we got were prepared in different reaction conditions. There is a characteristic absorption peak near 260 nm in UV spectra and there are two characteristic absorption peaks near 1 240 cm^-1 and 810 cm^-1 in the FT-IR. Degree of sulfation (DS) was calculated by elemental analysis and turbidimetry. Under the same conditions the absorption peaks become strong with the DS increase. The anticoagulant activity of SHG and sulfated modification samples was evaluated by the classic coagulant assays of prothrombin time (PT), activated partial thrombin time (APTT) live enzymes, and plasma thrombin time (TT). Results show that sulfated SHG has a good anticoagulant activity in vitro, and DS increased activity within a certain range.