Over the past years, Spirulina has gained popularity owing to its nutritional profile and bioactive ingredients. The advantages of employing Spirulina in aquafeeds as a feed ingredient or as a feed supplement to enhance fish performance in terms of growth and health have been extensively studied. Spirulina has an elevated protein content compared to plant sources of protein used in feed. As a result, it can be utilized as a substitute protein source in fish feed.  In addition, Spirulina contains a wide variety of bioactive ingredients with potential antioxidant, antimicrobial, anti-inflammatory and immunomodulatory activities. The present “Mini Review" emphasizes the significance of microalga use as a replacement for traditional aquafeed ingredients. The review also discusses how microalga-based feed additives have enormous prospects to enhance fish health, illness resistance and productivity. An overview of several pertinent studies on the usage of Spirulina in aquafeed and the ideal replacement level in fish diets is provided. All of the studies reviewed in the present work support the use of Spirulina as a viable nutritional supplement and a superior alternative protein source in fish feed, with several benefits. Spirulina integration with aquaculture systems appears to be a fantastic integrated fish-rearing approach. Future research could focus on examining the trade-offs associated with adding Spirulina to aquafeed, with a focus on sustainability analysis, product processing and acceptance.