In this paper, emulsion type sizing agents for carbon fiber were prepared by epoxy resin with the aid of various emulsifiers. Effects of emulsifier comprise and content on properties of emulsion were investigated by centrifugal sedimentation analysis and zeta potential measurement. Processing characteristics of desized and sized carbon fibers were compared. Results showed that the optimal emulsion was obtained when weight ratio of polyoxyethylene nonylphenol phosphoric ammonium (NP-10A) and polyoxyethylene styrenated phenol ether (602) was 2:1, ωe/r was 12%. The sizing agent emulsion could significantly improve the processability of carbon fibers due to the increase of abrasion resistance and flexibility of carbon fibers and the decrease of fluffs and breakage.