An acute febrile infectious disease occurred in a swine farm，with high fever（40.8-41.5 ℃），depressed spirit，inappetence，the skin flushing and cyanosed tip of ear，and so on，in March 2017 in Laiwu City of Shandong Province. To identify the infective pathogen，pathological examination，histopathological examination，molecular biology detection，virus isolation and identification were carried out，and molecular cloning，sequencing and homology comparison of E2 gene were performed on the isolated virus. It's diagnized as CSFV infection finally，and a strain named SDLW2017 was isolated. The results revealed that the E2 gene of SDLW2017 was 1 119 nucleotide（nt）in length and coded 373 amino acids（aa）. The similarity analysis of nucleotide and amino acid sequences revealed that SDLW2017 strain shared a nucleotide similarity of 82.1%-96.3% and an amino acid similarity of 88.5%-97.6% with other reference strains. The nucleotide and amino acid similarity of the HCLV strain with the 1.1 subpopulation were 82.1% and 88.5%，respectively. When compared with the subgenotype 2.1 strains，SDLW2017 strain shared higher nucleotide（91.8%-96.3%）and amino acid（95.2%-97.6%）similarities. The newly isolated strain shared the highest nucleotide（96.3%）and amino acid（97.6%）similarity with subgenotype 2.1b strain（GXWZ02）.