Vasoactive intestinal polypeptide (VIP) is known to be present in a subclass of GABAergic cortical interneurons. Here, using stereological analysis of VIP-stained sections, we investigated the distribution of VIP-positive (VIP+) interneurons across areas and layers of the marmoset cortex. Estimates of mean VIP neuronal density revealed an increasing trend from posterior to anterior cortex with prefrontal and frontal cortices having the highest VIP densities. Visual, posterior parietal and inferior temporal areas were characterised by lower VIP densities. VIP+ interneurons were more abundant in the supragranular layers and constituted ~2-8% of the total cortical neuronal population. These interneurons had different morphologies including bipolar, double bouquet and bitufted cells. Interestingly, we also found VIP to be present in the giant layer 5 pyramidal (Betz) neurons which are characteristic of the limb and axial representations of the marmoset primary motor cortex (cytoarchitectural area 4ab). The selective expression of VIP was indicated by the lack of VIP staining in smaller layer 5 pyramidal cells present in the primary motor facial representation (cytoarchitectural area 4c), or in the premotor cortex (e.g. the caudal subdivision of the dorsal premotor cortex, A6DC). Our results suggest that VIP interneurons are most abundant in the anterior cortical areas and demonstrate the expression of VIP in the largest excitatory neurons of the primate cortex, which may offer new functional insights into the role of VIP in the brain and provide opportunities for genetic manipulation of Betz cells.