Mathematical chemistry is a branch of theoretical chemistry in which we predict the mathematical structure by means of mathematical tools. In past few decades, many studies have been conducted in this area. This theory has cooperated a significant role in the field of chemistry. The main goal of this study is to calculate the weighted entropies of penta chains. We studied the graph entropies with Randić index, Zagreb indices, atom-bond connectivity, augmented Zagreb index, geometric arithmetic index, and sum connectivity index. We obtained the weighted entropies for the graphs formed of concatenated 5-cycles in one rows and in two rows of various lengths.