The synthesis of modified curcumin (17-[4-hydroxy-3-methoxylphenyl]-1,6-dine-3,5-heptaoxime)dione) by condensation reaction is reported.The properties of modified curcumin is studied with IR spectrum.The inter- reaction of curcumin(or modified curcumin)and hide powder(or mordant hide powder) are also investigated with differential scan calorimety (DSC)and stripping method. Resuts show the force of interaction between curcumin(modified curcumin)and collagen are hydrogen and wander waals force.The stability of moist heat of mordant hide porwer with rare earth with curcumin and modified curcumin marked rise. There may be stronger coordinate bond between modified curcumin and mordant hide porwer with rare earth.