Tilapias are the most farmed tropical fish species in the world, and production globally was about 4.5 million tons in 2013 and is predicted to exceed 6.6 million tons by 2030. The emergence of diseases has led to significant loss to tilapia aquaculture over the years. Medicinal plants have been known for use in treating some human diseases and studied in aquaculture to find safe and eco-friendly compounds that are suitable alternatives to the use of antibiotics and chemical compounds. Several parts including seeds, roots, flowers, leaves, and their extracts have been applied in tilapia aquaculture, administrated to fish through injection, immersion, and oral. The biological activities of medicinal plants include enhancement of growth and feed utilization, stimulation of the cellular and humoral immune response, gene expression, and increased disease resistance in tilapia. Despite the potential contribution of medicinal plants, there are some drawbacks including few commercially available medicinal products, no precise data on optimal dose requirements, lack of toxicity studies, and inadequate data on the effects of medicinal plants at the molecular level. This article describes the role of medicinal plants and their forms used to improve growth, feed utilization, immune response, and disease resistance as well as the prospects of medicinal plants in tilapia aquaculture.