Β-carotene, a major precursor of vitamin A (retinol), is a secondary metabolite which is found in all naturally occurring green plants, colored fruits and various microbial groups, including the microalgae. Microalgae, being a diverse group of organisms, are considered as a rich source of β-carotenoids. Dunaliella salina, a microalga, is commercially identified as a promising source of β-carotenoids. Chemically, β-carotene is a polyunsaturated hydrocarbon of 40 carbon atoms (C40H56), along with eight isoprene units and two β-ionone rings at both terminals. Worldwide, high demand for β-carotene due to its multiple therapeutic uses for diseases like light sensitivity, cataracts, severe pigmentation, aging of the skin, and cancer warrants its mass production. This chapter discusses about the revolution of β-carotene production by developing the cultivation of the algae, followed by organic solvent extraction. Usually, β-carotene is procured by saponification with calcium hydroxide or acetone solubilization-purification. The chapter reviews on how the newer harvesting and extracting technologies such as use of photobioreactor, chemostat, nano emulsion along with AI models, e.g., artificial neural networks (ANN), support vector machines (SVM), and adaptive neurofuzzy inference systems (ANFIS) has been employed for obtaining quick, accurate, and exact analytical results.