Oxytocin (Oxt) neurons regulate diverse physiological responses via direct connections with different neural circuits. However, the lack of comprehensive input-output wiring diagrams of Oxt neurons and their quantitative relationship with Oxt receptor (Oxtr) expression presents challenges to understanding circuit-specific Oxt functions. In this talk, I will first present my lab’s effort to understand spatiotemporal trajectories of Oxtr expression in postnatally developing mouse brains, anatomic connectivity maps of Oxt neurons, and their relationship with Oxtr expression. I developed and utilized high resolution mapping methods to visualize and quantify cellular resolution signals across the entire mouse brain using 3D reference atlases. Our detailed Oxt wiring diagram provides anatomic insights about the distinct behavioral functions of Oxt signaling in the brain. Secondly, I will present our ongoing effort to understand the anatomy and function of Oxtr neurons in the dorsal endopiriform nucleus (EPd). The EPd is a largely understudied cortical subplate area that contains a high density of Oxtr neurons. We are utilizing a combination of a cell type specific Cre driver, viral tools, 3D mapping methods, and in vivo neural activity recording to comprehensively gain novel insight of the EPd neurons. We found strong EPd connectivity with olfactory and limbic cortices and identified a sustained decrease in neural activity upon novel stimuli. Collectively, our research advances neuroanatomical understanding of Oxt system in the brain and how it regulates different behaviors.