The cerebral cortex, consisting of six layers, plays a key role in higher brain functions such as motor planning, sensory processing, emotions, and consciousness. Classification of neuronal subtypes based on morphological, physiological, and genetic features is an indispensable process in understanding the mechanism of higher-order cerebral function.Neocortical pyramidal neurons in layer 2/3 (L2/3) integrate information from numerous brain regions and provide the majority of input to layer five neurons, facilitating information exchange with other cortices. Despite recent advances in genetic tools over the past few decades, little has been reported on the neuronal classification of L2/3 due to its morphological and functional heterogeneity.Here we present the novel neuronal subtype in L2/3 of the prefrontal cortex. We evaluated cell density and neuronal soma size in L2/3 of several cortical areas, as well as hierarchical cluster analysis based on electrophysiological properties. The prefrontal cortex, but not other cortical areas, has a sparse cell-density layer in L2/3. Pyramidal neurons in this sublayer have large neuronal somas and exhibit a burst-firing characteristic.The prefrontal cortex is the most evolved brain region that serves as the substrate of the highest cognitive function and is associated with many mental disorders. To elucidate the role of the burst-firing subtype in the prefrontal cortex, we will search for cell type-specific genes using the patch-seq technique for precise manipulation of this novel cell type.