The red seaweed group (Rhodophyta) is one of the phyla of macroalgae, among the groups Phaeophyceae and Chlorophyta, brown and green seaweeds, respectively. Nowadays, all groups of macroalgae are getting the attention of the scientific community due to the bioactive substances they produce. Several macroalgae products have exceptional properties with nutraceutical, pharmacological, and biomedical interest. The main compounds studied are the fatty acids, pigments, phenols, and polysaccharides. Polysaccharides are the most exploited molecules, which are already widely used in various industries and are, presently, entering into more advanced applications from the therapeutic point of view. The focuses of this review are the red seaweeds’ compounds, its proprieties, and its uses. Moreover, this work discusses new possible applications of the compounds of the red seaweeds.