The goal of the Maximum Diversity Problem (MDP) is to determine the largest diverse set of a particular size from a given weighted graph. The target here is to maximize the sum of edge weights of a certain number of selected vertices from a graph. To solve the maximum diversity problem, we presented a metaheuristic method based on Chemical Reaction Optimization (CRO) in this paper. A population-based metaheuristic for resolving optimization problems is the CRO algorithm. It can explore the solution space over the population both locally and globally with the aid of its four response operators. A dataset with three separate group instances is used to evaluate the performance of our suggested method, which produces superior results with lower average errors than state-of-the-art methods.