<p>The human population is increasing at an alarming rate, such that it is expected to surpass nine billion in the coming decades. This has led to an increasing demand for high-protein food sources like meat and eggs. Hence, this demand for high-protein food will amplify the exploitation of traditional animal feed crops like maize, rice and soybean, which in turn can lead to their scarcity. Thus, we need an alternate animal source in order to guarantee proper food security and sustainability. In this scenario, microalgae become a practicable solution because they possess a rich nutrient profile and only require environmentally friendly cultivation methods. Microalgae are unicellular, photosynthetic organisms known for their valuable nutrient content. They are rich sources of proteins, essential fatty acids, vitamins, and antioxidants. Their ability to proliferate rapidly in diverse environments, minimal land requirement and low maintenance make them a perfect substitute for conventional animal feeds. Our review mainly discusses microalgae’s potential role in improving the currently available options for animal feeds. We have also evaluated the studies on microalgal-based animal feeds to see how their incorporation in the animal feeds enhanced their growth performance, feed efficiency, and overall health. Further, we have reviewed the latest microalgal genetic engineering techniques that can help improve animal feed quality. Therefore, using these advancements in the animal feeding industries, we will be able to improve animal health and productivity, which is likely to improve human welfare in the future.</p>