<p>This study was conducted to evaluate the effect of mulberry leaves (ML) as an alternative source of clover hay on growth performance, nutrient digestibility, carcass traits, and blood parameters of Flanders rabbits. Thirty-six growing rabbits were randomly and equally divided to be fed three diets as follows: basal diet (control, ML0), basal diet with mulberry leaves as a replacement for clover hay by either 9% (ML9) or 12% (ML12) for 63 days as growth trials. Three animals in each group were slaughtered to assess the carcass traits and determine some blood parameters at the end of the experiment. Results indicated that ML decreased (<i>P</i> &lt; 0.05) dry and organic matter digestibility and increased ether extract digestibility compared to the control group. At the same time, there were no significant differences in the other nutrients’ digestibility and nutritive value, such as digestible crude protein, among groups. The discrepancies between feeding groups in final body weight, average daily gain, and dressing percentage lacked significant. All blood parameters were in the normal range, where the cholesterol, triglyceride, total lipids, and antioxidant capacity were recorded at the lower concentration (<i>P</i> &lt; 0.05) for ML9 and ML12 compared with ML0. Additionally, using mulberry leaves at a 12% substitution decreased the feed cost and increased the economic efficiency. It can be concluded that mulberry leaves can be used in place of clover hay in growing rabbits’ diets up to 12%.</p>