Abstract: Ammonium thiocyanate method was applied to determine coating efficiency for carboxymethyl chitosan coated liposomes. The result showed that the wavelength for determination of phospholipid was at 470nm . At the concentration range of 0 . 01 ~ 0 . 1mg / mL , the content of phospholipid showed good linear relationship with the absorbance. Before determination, the uncoated liposomes were isolated from the coated ones by centrifugation operated at 10000r/min for 15min and broken by alcohol-ultrasound method with 0.8mL of ethanol and ultrasonication for 15min. Through recovery, precision, and reproducible experiments proved that the method was feasible.