Natural bioactive compounds derived from plant-based products are known for their biological immunomodulatory activities. They possess systemic pleiotropic effects, minimal side effects, and very low toxicities. Plant-based bioactive compounds have tremendous potential as natural therapeutic entities against various disease conditions and act as anti-inflammatory, antioxidant, anti-mutagenic, anti-microbial, anti-viral, anti-tumour, anti-allergic, neuroprotective, and cardioprotective agents. A herbal formulation extract including five biologically active compounds: Apigenin, Quercetin, Betulinic acid, Oleanolic acid, and β-Sitosterol can impart several immunomodulatory effects. In this review, we systematically present the impact of these compounds on important molecular signaling pathways, including inflammation, immunity, redox metabolism, neuroinflammation, neutropenia, cell growth, apoptosis, and cell cycle. The review corroborates the beneficial effect of these compounds and shows considerable potential to be used as a safer, more cost-effective treatment for several diseases by affecting the major nodal points of various stimulatory pathways.