Optical imaging is a noninvasive and safe technique that can be applied for live imaging and as diagnostic tool. In particular the near infrared (NIR) spectral region between 700 and 1400,nm, where minimal scattering and absorption of biological tissue is present, is highly desired to achieve high-resolution images and deep-tissue penetration. In this chapter we will focus on carbon nanomaterials (CNMs) as fluorescent tags for NIR imaging highlighting recent developments in this fields. Their high photostability, intrinsic fluorescence, and biocompatibility, make these nanomaterials promising imaging probes.