This chapter describes the potential of various shapes of gold nanomaterials such as nanoparticles, nanorods, nanostars, nanocages, and nanoshells in cancer nanotheranostics, i.e., both as diagnostic and therapeutic agent. This study includes the synthesis of different gold nanomaterials using several methods like chemical-, green-, and microbial-mediated synthesis. The ability of gold nanomaterials to absorb light in the near-infrared region and transform it into heat and their unique optical properties make them a promising tool in photothermal cancer therapy. Herein, we present the recent advances and the ability of gold nanomaterials to show its multiple roles in the field of cancer biology. © 2017 Elsevier Inc. All rights reserved.