A waterborne polyurethane／A-stage phenolic resin dispersion was prepared．The relationship between pH value and the solubility of the phenolic resin in water indicated that the dissolution of A-stage phenolic resin resulted from the ionization of the phenolical hydroxyl groups in basic solution．There were three kinds of granules in the waterborne polyurethane／A-stage phenolic resin dispersion：core-shell

incomplete core-shell and pure polyurethane

depending on the condensation degree and the amount of phenolic resin．The average diameter of the particles in the dispersion and the distribution width of particle size became greater and wider

respectively

with increasing the proportion of phenolic resin

while the stability of the dispersion with regard to heat

mechanical effect and freezing-melting process and the C.C.C value decreased．It Was proved that the stability of the dispersion was determined mainly by the electrical properties of the dispersion

therefore it should belong to real sol

but

to some extent

the dispersion also had some properties of macromolecular solutions．The properties of the coating film prepared by the polyurethane／phenolic resin dispersion were superior to those made of pure PU film

and could modified further by hybridization with SiO2-sol.