Omega-3 fatty acids are a large group of unsaturated fatty acids with long carbon chains and multiple double bonds in their structure (PUFAs). Omega-3 fatty acids, which include docosahexaenoic acid (DHA), eicosapentaenoic acid (EPA), and α-linolenic acid (ALA), are essential polyunsaturated fatty acids with a wide range of health benefits. These fatty acids confer unique fluidity, permeability, and flexibility properties to cellular membranes. DHA has antiarrhythmic and anti-inflammatory properties that play a significant role in promoting cardiovascular health. Furthermore, the consumption of DHA is linked to enhanced vision, cognitive function, and memory development. In addition, this fatty acid offers protection against a range of health conditions such as depression, Alzheimer’s, heart diseases, thrombosis, hypertension, celiac disease, diabetes, and certain types of cancer. Within bacterial sources, oleaginous actinomycetes, microalgae like Thraustochytrids, Crypthecodinium, and Nannochloropsis, reveal their capacity to store up to 50% of their dry weight in lipids. The microbial production of DHA offers a promising solution to meet global demand, and the biosynthesis of DHA involves both aerobic and anaerobic pathways. Optimization of physicochemical parameters, including carbon and nitrogen sources, pH, temperature, and salinity, is essential for maximizing DHA production in microbial systems. The fine-tuning of these parameters can significantly impact the efficiency of DHA production processes. Microbial sources show great potential in addressing the global demand for omega-3 fatty acids, providing an effective and sustainable approach to improving human health through the production of essential fatty acids like DHA.