Through aerobic and anaerobic cultivation, pure culture of a bacterial strain named HN1203 suspected to be Bacillus cereus (B. cereus) was isolated from liver sample of a piglet recovered from severe post-wean diarrhea syndrome. Analyzing of 16S rRNA sequence (GenBank accession number JX294967) of HN1203 showed this strain belongs to type 7 of Bacillus cereus group. Biochemical identification indicated biochemical characteristics of HN1203 are accord with that of the strains of B. cereus group. Drug susceptibility testing and parasporal crystal protein test showed that this strain was sensitive to tetracycline and streptomycin, resistant to penicillin, and no parasporal crystal was formed on the spore of HN1203. Multilocus sequence typing (MLST) assays revealed a new allele of house-keeping gene pta, which was assigned a new sequence type (ST) of 611. PCR detection showed HN1203 harbors virulence-coding genes hblCDA, nheABC, cytK and entFM. These results showed HN1203 is a now B. cereus strain, and isolation of which indicated that normally used aerobic condition is not suitable for isolation of B. cereus. Further animal test showed HN1203 could be fatal to mice. These findings highlight the need of increased awareness of pathogenic B. cereus in pig and its zoonotic potential.