The effects of milk supplementation with catfish bone hydrolysate (CBH) at levels of 0, 0.05, 0.15, and 0.5 % on the pH, lactic acid bacteria count (LABC), fermentation time, texture attributes and microstructure of yogurt were investigated. The addition of CBH stimulated acidification and reduced fermentation time (P < 0.05). In comparison with the control yogurt, CBH caused a decrease in product firmness, consistency, cohesiveness and index of viscosity/consistency. The additon of 0.5% CBH produced a higher decrease (P < 0.05). Scanning electron microscopy showed that CBH caused changes in microstructure of yogurt that had a coarser, less cross-linked microstructure than control yogurt.