Abstract: Addressing the challenge of coordinated voltage optimization control in high and medium voltage distribution networks with high penetration of photovoltaic (PV) integration, this paper proposes a hierarchical distributed voltage chance-constrained optimization method. In contrast to the typical independent voltage control architecture of high and medium voltage distribution networks, a novel hierarchical distributed voltage control architecture suitable for high PV penetration is designed. At the medium voltage distribution network level, considering both the uncertainty of distributed PV output and the efficiency of probability function solving, a quickly computable quadratic programming model based on chance constraints is constructed. Finally, comprehensive verification of the efficacy and precision of the newly-proposed methodology was conducted through an enhanced IEEE 33-node benchmark system.