The waxy corn starch was used to prepare hydroxypropyl and octenyl succinic anhydride compound modified starch.The physical properties of waxy corn hydroxypropyl and octenyl succinic anhydride compound modified starch were investigated by Fourier transform infrared spectrometer(FT-IR),scanning electron microscope,X-ray diffraction(XRD),Brabender viscometer and so on.The results indicated that the FT-IR spectrum of compound modified cassava starch showed new absorption peaks at 1 550 ~ 1 610 cm-1,1 714 cm-1,demonstrating the introduction of RCOO—and C=O groups.The surface of the starch granule exhibited rougher and more irregular shape,but the crystalline structure was not changed.The transparency,freeze-thaw stability,emulsifying and emulsion stability after compound modification.