Using tilapia trim meat (TTM), a by-product from industrial-scale tilapia fillet manufacturing, for production of fermented fish sausage (FFS) may increase the benefit to the tilapia filleting industry by selling this new product to consumers. Six ratios of TTM:tilapia fillet meat (100:0, 80:20, 60:40, 40:60, 20:80 and 0:100) were used for sausage production. FFS samples prepared with each ratio were collected on days 0, 2, 4 and 6, and analyzed for quality parameters including lactic acid bacteria (LAB), total plate count (TPC), yeast and mold (YM), texture profile analysis (TPA), CIE color values (L*, a* and b*), pH, titratable acidity and sensory acceptability. The ratio of TTM to tilapia fillet
meat had no effect on YM, b*, pH and titratable acidity. The 0:100 ratio produced lower LAB, TPC and L* values compared to 100:0, 80:20 and 60:40. The ratio also yielded a higher a* than 100:0 and 80:20. The 0:100 ratio generated the best TPA, followed by 20:80. However, these two ratios were not significantly different concerning sensory acceptability. The 20:80 ratio, giving similar sensory quality to 0:100, is recommended for the production of FFS. The results also reveal that FFS ripened on day 2 and ratios of TTM:tilapia fillet meat did not affect the ripeness of the product. The best quality of FFS was found on day 4.