We modified urea-formaldehyde resin( UF) by oxidized corn starch,studied the effect of oxidized starch addition on the properties of UF. To obtain the best optimal conditions,we evaluated bonding strength of plywood and free formaldehyde content of UF resin and plywood. The free formaldehyde content of plywood and UF resin decreased. And the oxidized starch added was beneficial for improving bonding strength of plywood. The optimal condition to prepare UF with best performance was with the oxidized starch a...