Chemical fertilizer application is one of the most common practices worldwide due to its fast nutrient release mechanism. Nevertheless, the usage of inorganic fertilizer for vegetable crops is not preferred as it may contribute to the health risk. A field experiment was conducted to evaluate the effect of different concentrations of fish amino acid (FAA) as foliar fertilizer on the growth and yield of kale (<i>Brassica oleracea</i> var. alboglabra L). Five treatments of the experiment were; T1 NPK Green (Control), T2 (10% FAA), T3 (20 % FAA), T4 (30 % FAA) and T5 (40 % FAA). The growth performance of kale when treated with T4 showed significantly higher (<I>P <</I> 0.05) plant height, number of leaves, number of branches, total leaf area, and plant biomass as compared to other treatments. Fish amino acid at 30 % concentration can be recommended as an effective replacement for NPK green for sustainable kale production.