This study was intended to investigate whether Hericium erinaceus polysaccharides (HEP) prevent oxidative stress and apoptosis of intestinal porcine epithelial cells from jejunum (IPEC-J2 cells) induced by hydrogen peroxide (H2O2). Crude HEP were extracted and purified by chromatography. The ultraviolet and infrared spectra and monosaccharide composition of HEP were analyzed. Reactive oxygen species (ROS) generation was quantified by flow cytometry method, and lactate dehydrogenase (LDH) and malondialdehyde (MDA) production were determined by TBARS. Also, apoptosis was analyzed by flow cytometry method and the apoptosis-related regulatory molecules were determined by microplate or western blotting method. Our results showed that pretreatment of IPEC-J2 cells with HEP significantly scavenged ROS and reduced LDH and MDA production. HEP also reduced apoptosis and kept polarity of the mitochondrial membrane potential. Moreover, HEP increased the content of caspase-3 and PARP, and protein expression of Bcl-2, while inhibited Bax and Bad and reduced the content of caspase-9 and release of CytC. Meanwhile, HEP inhibited the protein expression of TNFR1, FAS, and FASL, and decreased the content of caspase-8. The results indicated that HEP had a protective effect against oxidative stress in IPEC-J2 cells and the underlying mechanism was reducing apoptosis via mitochondrial and death receptor pathways.