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The purpose of this paper is to guide lectors in the extraction of algal (microalgae and seaweeds) compounds using supercritical carbon dioxide (SC-CO 2 ) from dry biomass. It proposes a review of ∼30 articles dealing with the SC-CO 2 extraction of molecules of interest from microalgae and seaweeds. Among these papers, ∼20 are devoted to microalgae. The most extracted compounds are neutral lipids and antioxidants. Several operating conditions have been tested: pressures from 7.8 to 70 MPa, temperatures from 313.15 to 349.15 K, and CO 2 /algae mass ratio from 6 to 500. All extraction studies were performed at laboratory scale, with the masses of dry algae powder never exceeding 180 g. Extraction yields vary significantly with operating conditions: pressure seems to be the most influential parameter. The higher the pressure, the higher the yields and/or the faster the extraction kinetics. Temperature also has an influence, but its effect is dependent on pressure (retrograde behavior). Moreover, as expected, it is advised to work with a high CO 2 /algae mass ratio. From these works, it appears that, to perform an efficient extraction with SCÀCO 2 , the influence of the algae pretreatment is highly significant. The first step is a centrifugation. The resulting concentrated algal suspension must then undergo a drying operation, which is generally freeze-drying or low-temperature drying. Finally, the algae are crushed. Concerning the influence of crushing, the reported results show that, as expected, the smaller the particles, the more rapid the extraction kinetics and/or the higher the yields.