The present invention provides an aqueous coating composition comprising (i) particles of a non-melt processible polymer of tetrafluoroethylene and (ii) a non-fluorinated polymer selected from the group consisting of a polysulfone, a polyamide, a polyimide, a polyamide-imide, a polybismaleimide and mixtures thereof, wherein said particles are core-shell particles whereby the shell comprises a copolymer of tetrafluoroethylene and a partially fluorinated or non-fluorinated comonomer. The aqueous coating composition may be used for providing a primer coating on a substrate such as a metal or glass substrate. Such primer coating may provide good or excellent non-stick coatings combined with good or excellent scratch and wear resistance of the coating. Also, such primer coating may provide for good to excellent PTFE coatings that can resist hot salt water. The aqueous coating composition may also be used to provide other coating layers of a multi-layer coating.