The aim of this research was to evaluate the effect of different concentrate levels in diets based on cactus Opuntia Stricta (Haw.) Haw cladodes on the performance of lactating Girolando cows. Methods: The experiment involved 10 Girolando multiparous dairy cows at 512.6 kg of body weight (BW) and producing 13.2 kg milk/d, allocated into two 5×5 Latin squares. The experi mental treatments consisted of control diet composed by cactus Nopalea cochenillifera. Salm Dyck. cladodes (Nopalea), forage sorghum silage and concentrate at 20% on dry matter (DM) basis, and four concentrate levels diets (20%, 24%, 28%, and 32%) plus cactus Opuntia stricta (Haw.) Haw. cladodes (Opuntia) and forage sorghum silage. Results: Regarding cows fed control diet, the nutrients intake were greater than for cows fed with cactus Opuntia and concentrate. Regarding concentrate levels, intakes of DM, organic matter (OM), crude protein (CP), nonfiber carbohydrates (NFC), and total digestible nutrients of cows increased linearly. Organic matter, CP, and NDF digestibilities were similar in between to control diet and cactus Opuntiabased diets. The digestibility of NFC increased linearly when the concentrate was inserted. The N balance was the same for control diet and cactus Opuntiabased diets, irrespective the concentrate levels. Conclusion: For cows producing 14 kg/d with 3.5% of fat, it is recommended 32% of con centrate to be included in cactus Opuntiabased diets, and the increase in concentrate level promotes a linear increase in milk yield.