The synthesis and integration of core-shell materials have been extensively explored in three-dimensional nanostructures, while they are hardly ever extended into the emerging two-dimensional (2D) research field. Herein, demonstrated by graphene (G) and hexagonal boron nitride (h-BN) and via a sequential chemical vapor deposition method, we succeed for the first time in synthesizing 2D h-BN-G core-shell arrays (CSA), which possess extremely high uniformity in shapes, sizes and distributions. Each of the core-shell units is composed of G ring-shaped shell internally filled with h-BN circular core. In addition, we perform simulations to further explain the self-symmetrical etching growth mechanism of the h-BN-G CSA, demonstrating its potential to be used as an efficient synthetic method suitable for other 2D CSA systems.