Microglia are the inflammatory cells of the brain and are activated in neuropathological conditions. To study the biology of microglia, these cells can be isolated from the brain and analyzed in terms of pro- and anti-inflammatory cytokine production, involvement of intracellular signaling pathways upon inflammatory stimuli, phagocytosis, and several more biological aspects to understand their role in the brain. In this book chapter, I will discuss microglial cells and describe how these cells can be cultured from a postnatal mouse and rat brain.