•A Chinese virulent genotype GIIb PEDV strain, CH/HNPJ/2017, was successfully separated and serially propagated in Vero cells.•The biological characteristics and pathogenicity of PEDV strain CH/HNPJ/2017 were determined.•The median pig diarrhea dose (PDD50) of Chinese PEDV strain was first determined.•The immune protective effect of PEDV strain CH/HNPJ/2017 as vaccine candidates was also be evaluated. Since October 2010, severe porcine epidemic diarrhea (PED) outbreaks caused by highly virulent PED virus (PEDV) strains have occurred continuously in the Chinese pig population and caused considerable economic losses. Although PEDV vaccines based on classical PEDV strains have been widely used in China in recent years, the morbidity and mortality in piglets remain high. Therefore, virulent genotype GII PEDV strains that are prevalent in the field should be isolated and used to develop next-generation vaccines. In the present study, a Chinese virulent genotype GIIb PEDV strain, CH/HNPJ/2017, was serially propagated in Vero cells for up to 90 passages. The S genes contained typical insertions and deletions that were also found in other recently isolated highly virulent PEDV strains from China and other countries and had two neighboring unique insertion mutations, which resulted in four amino acid changes in the S1 region of passages P10 and P60. Pig infection studies revealed that the CH/HNPJ/2017 strain was highly virulent in piglets, and the median pig diarrhea dose (PDD50) was 7.68 log10PDD50/3 mL. Furthermore, the cell-adapted CH/HNPJ/2017 strain elicited potent serum IgG and neutralizing antibody responses in immunized pigs when it was used as an inactivated vaccine candidate. In addition, the pigs that received the experimental inactivated vaccines were partially protected (3/5) against subsequent viral challenge. In brief, these data indicate that the CH/HNPJ/2017 strain is a promising candidate for developing a safe and effective PEDV vaccine in the future.