Bropirimine, a class of antineoplastic agents, is known as one of the potent immunomodulators and is currently under clinical development for the treatment of cancer. However, the effect of bropirimine on the cow remains unknown as a therapeutics agent. In this experiment, the effect of bropirimine in the peripheral blood mononuclear cells (PBMCs) stimulated by lipopolysaccharide (LPS) or concanavalin-A (Con-A) was examined. Jugular venous blood was collected from Korean Hanwoo calves and PBMCs were isolated. It was used to study the effect of bropirimine upon stimulation with LPS or Con-A for 72 hours. The expression pro-inflammatory cytokines like Tumor Necrosis Factor α (TNF-α) and Interferon γ (IFN-γ) were confirmed. Bropirimine significantly inhibited LPS- or Con-A-induced TNF-α and Con-A-induced IFN-γ in dose-dependent manner. Furthermore, Bropirimine inhibited TNF-α and Con-A mRNA expression at the transcription level. These results clearly indicated that bropirimine inhibited LPS or Con-A stimulated up-regulation of proinflammatory cytokines in a dose-dependent manner without conspicuous cytotoxicity. The bropirimine has potential to protect cow from LPS or Con-A induced endotoxin shock, possibly through inhibition of the production of proinflammatory cytokines. It suggesting that bropirimine may be a novel therapeutic agent for the prevention of inflammatory diseases. This result revealed specific features of the immune responses depending on the bropirimine compound and would help to knowledge of bovine immunity.