Corals are holobiont animals, that is, they live in association with other organisms that perform essential functions for their survival. This symbiotic community of corals is mainly composed of microorganisms (bacteria and archaea) and microalgae (dinoflagellates from the Symbiodiniaceae family). These microorganisms act in protection against pathogens, in the cycling and availability of nutrients and provide a large part of the host's nutritional supply, and are fundamental for maintaining homeostasis and adaptability of the holobiont to environmental changes. Understanding the composition of symbionts of a given coral species is essential to understand evolutionary, adaptive, metabolic and regulatory processes, especially in scenarios of climate change and environmental impacts. The main tools used to access this community are molecular approaches, mainly metabarcoding through next generation sequencing (NGS). During the lecture, the main molecular and analytical approaches used in the study of symbiotic coral communities will be presented, as well as their advantages and challenges.