Cellular polarity is a fundamental feature of many types of cells that describes the asymmetric distribution of its components within a cell. Classical examples of polarized cells include epithelial cells, neuron, and migratory cells. Cellular polarity is required to ensure the cells response accordingly to the cues arises from neighbouring cells or microenvironments. Past works had shown that disruption of cell polarity can cause cells irresponsiveness to stimulating and inhibiting signals or in the worse scenario, cell apoptosis. Despite its critical role in normal cell functions, little is known about the cellular polarity in pancreatic islet. This study is designed to investigate the cellular polarization in insulin secretion islets. Using live cell 2-photon imaging of intact islets, we showed that optical slice contains asymmetrical, non random distribution sites of insulin granule fusion (Chi Square P<0.01). Using multi-planar live cell 2 photon imaging, we show that insulin granules are fused preferentially at the vasculature region. Our three-dimensional immunofluorescent of islet slices show that structural proteins associated with presynaptic targeting are found in pancreatic β cell islet and have a polarized distribution with enrichment in the region that faces the vasculature. Our results show that β cells in situ within an islet are polarized and target insulin secretion will have wide implications on our understanding of stimulus secretion coupling in healthy islets and in disease.