Fish has industrial and economic importance as a food source and fishing industry. The usage of fish such as tilapia and catfish to produce healthy fillets and other substances with nutritional and economic importance is a promising business in Egypt. Annually, large amounts of by-products could be procured from tilapia and catfish processing. In this study, skin of two types of famous and cheap fish species in Egypt Nile tilapia (Oreochromis niloticus) and catfish were used for gelatin extraction. The quality of the gelatins was estimated and used as an edible film to prolong the storability of refrigerated tilapia fillets. The results showed that both tilapia and catfish gelatins had good chemical properties (yield, protein content, ash, fat, color, and amino acid composition), and increased the shelf life of fish fillet when has been used as an edible coating. Both types of gelatins reduced the weight loss of fish fillets, maintained and improved the fillet color, and had good sensory properties compared to the control under cold storage. No significant differences between tilapia and catfish gelatins had been reported for most studied parameters. Thus, the skin by-products of tilapia and catfish can be used to produce good quality gelatins that could be efficiently used as an edible coating to improve the storability of fillet fish.