The montmorillonite (MMT) was treated by cetyl trimethyl ammonium bromide (CTAB) and dodecyl trimethyl ammonium bromide (DTAB) to obtain the organophilic montmorillonite (OMMT), and then the organophilic montmorillonite/urea-formaldehyde resin (OMMT/UF) was prepared by intercalated composite method during the polymerization process. The XRD and SEM showed that the organic reagent has intercalated into the layers of MMT, and the interlayer space of OMMT modified by CTAB and DTAB is larger than that of MMT. The influences of OMMT content on apparent viscosity, water resistance, curing time and free-formaldehyde content were discussed. The results showed that the apparent viscosity is 2 times of UF, the water resistance time of OMMT/UF is 100 min more than UF, the free-formaldehyde content is 5.6 mg/L which is much lower than UF, but the curing time increases to 118 min, when the OMMT content is 3~5%. Plywood prepared by using OMMT/UF as adhesive was discussed, which showed that the OMMT/UF can significantly improve the strength of the plywood and reduce the release of formaldehyde.