Marine　microalgae　are　regarded　as　potential　feedstock　because　of　their　multiple　valuable　compounds,　including　lipids,　pigments,　carbohydrates,　and　proteins.　Some　of　these　compounds　exhibit　attractive　bioactivities,　such　as　carotenoids,　ω-3　polyunsaturated　fatty　acids,　polysaccharides,　and　peptides.　However,　the　production　cost　of　bioactive　compounds　is　quite　high,　due　to　the　low　contents　in　marine　microalgae.　Comprehensive　utilization　of　marine　microalgae　for　multiple　compounds　production　instead　of　the　sole　product　can　be　an　efficient　way　to　increase　the　economic　feasibility　of　bioactive　compounds　production　and　improve　the　production　efficiency.　This　paper　discusses　the　metabolic　network　of　marine　microalgal　compounds,　and　indicates　their　interaction　in　biosynthesis　pathways.　Furthermore,　potential　applications　of　co-production　of　multiple　compounds　under　various　cultivation　conditions　by　shifting　metabolic　flux　are　discussed,　and　cultivation　strategies　based　on　environmental　and/or　nutrient　conditions　are　proposed　to　improve　the　co-production.　Moreover,　biorefinery　techniques　for　the　integral　use　of　microalgal　biomass　are　summarized.　These　techniques　include　the　co-extraction　of　multiple　bioactive　compounds　from　marine　microalgae　by　conventional　methods,　super/subcritical　fluids,　and　ionic　liquids,　as　well　as　direct　utilization　and　biochemical　or　thermochemical　conversion　of　microalgal　residues.　Overall,　this　review　sheds　light　on　the　potential　of　the　comprehensive　utilization　of　marine　microalgae　for　improving　bioeconomy　in　practical　industrial　application.　©　2020　by　the　authors.　Licensee　MDPI,　Basel,　Switzerland.