Regulations for the energy consumption of printers and copiers are getting more severe year by year. And with increasingly faster machine systems, the fusing of toner on the paper gets more difficult, so the toner which can be fused with lower energy is needed. Crystalline polyester (C-PES) is known as a very effective agent for toner fusing. C-PES dispersion size in toner is very important for fusing, and nano size CPES which shows very good fusing was reported by Fukuri et al. On the other hand, chemically prepared toner (CPT,) especially emulsion aggregation toner (EA), was studied a lot in recent years. Toner from EA method can allow toner with coreshell structure, for example a low-Tg resin core that is covered with high-Tg resin shell. Therefore EA method is expected to provide both low energy fusing and good storage stability. In this report, the study of CPT toner containing C-PES is done. The effect of conventional C-PES for CPT was very poor, so we studied the melting point of C-PES for improved performance in CPT. While studying the EA toner containing C-PES, it was observed that the particle size of C-PES emulsion is very sensitive to neutralization level. We evaluated several ways to prepare better C-PES emulsions by controlling the hydrogen bonding of C-PES during emulsification.