This paper aims to study two approximation theorems in view of the periodic averaging results for non‐Lipschitz multivalued stochastic differential equations with impulses and G‐Brownian motion (MISDEGs). By adopting G‐Itô’s formula and non‐Lipschitz condition, the solutions to the simplified MSDEGs without impulses may replace those of the initial MISDEGs in view of approximation in L2‐sense and capacity. Finally, we bring a couple of two examples to enhance our theoretical results.