Microalgae belong to autotrophic microorganisms that live in marine, freshwater, and soil ecosystems and produce organic substances through photosynthesis. Due to their high metabolic flexibility, adaptation to different growing conditions, and ability to grow quickly, the number of research studies on their use as a source of biologically valuable products is rapidly increasing. Currently, the most interesting studies are integrated technologies for microalgae cultivation to isolate various biologically active substances from biomass, thereby increasing microalgae production's profitability. Particularly interesting are industrial cultivation systems with high productivity, which must be accompanied by the ability to biologically control the biosynthesis of high-value compounds under conditions of intensive culture growth. This paper presents the main factors (temperature, pH, medium composition) that affect the biomass growth process and the synthesis of biologically active substances in microalgae. Cultivation methods describe the advantages and disadvantages of existing ones and different methods for isolating the main biologically active substances of microalgae (proteins, lipids, polysaccharides, pigments) and vitamins). New technologies and approaches for using microalgae as ingredients in value-added products are presented.