Dendrimers recently emerged as a strong category of nanoparticles in the realm of nanomedicine due to their distinct structural properties. In order to bring the medications to mark the carrier vehicle, a specific design with the right qualities (topological invariants) might be targeted using the physical chemistry of dendrimers. Topological descriptors of chemical networks are numeric numbers that allow us to obtain information about a compound’s structure and expose its underlying properties without the requirement for validation. In this work, we have computed the atom-bond connectivity index (ABC) and the atom-bond sum-connectivity index (ABS) of bismuth(III) iodide and PETAA dendrimer. A graphical comparison is given at the end to study the behavior of these two topological indices for bismuth (III) iodide and PETAA dendrimer.