Red ginseng, which has a variety of biological and pharmacological activities including antioxidant, anti-inflammatory, antimutagenic and anticarcinogenic effects, has been used for thousands of years as a general tonic in traditional oriental medicine. Here, we tested the immune regulatory activities of hydrolyzed red ginseng by malted barley (HRG) on the expressions of receptor interacting proteins (Rip) 2 and $I{kappa}B$ kinase-beta (IKK-${eta}$) in mouse peritoneal macrophages. We show that HRG increased the activations of Rip 2 and IKK-${eta}$ for the first time. When HRG was used in combination with recombinant interferon-${gamma}$ (rIFN-${gamma}$), there was a marked cooperative induction of nitric oxide (NO) production. The increased expression of inducible NO synthase from rIFN-${gamma}$ plus HRG-stimulated cells was almost completely inhibited by pre-treatment with pyrrolidine dithiocarbamate (PDTC), an inhibitor of nuclear factor-${kappa}B$ (NF-${kappa}B$). In addition, the treatment of peritoneal macrophages with rIFN-${gamma}$ plus HRG caused significant increases in tumor necrosis factor (TNF)-${alpha}$ mRNA expression and production. Because NO and TNF-${alpha}$ play an important role in the immune function and host defense, HRG treatment can modulate several aspects of the host defense mechanisms as a result of the stimulations of the inducible nitric oxide synthase and NF-${kappa}B$. In conclusion, our findings demonstrate that HRG increases the productions of NO and TNF-${alpha}$ from rIFN-${gamma}$-primed macrophages and suggest that Rip2/IKK-${eta}$ plays a critical role in mediating these immune regulatory effects of HRG.