Buriti (Mauritia flexuosa) oil can be a great energy source for goats in lactation. This study aimed to determine the most effective level of buriti oil to use in supplements for lactating goats. Eight Anglo-Nubian crossbreed goats in 50 d of lactation were grouped into 2 4 × 4 double simultaneous Latin squares being 4 experimental periods of 21 d each, with 16 adaptation days and 5 d data collection. The treatments were 4 diets containing 0–15, 30 or 45 g·kg⁻¹ of buriti oil in the total diet. The diets, a total mixed ration, were composed of corn silage and concentrate made with: corn, soybean, mineral supplement and buriti oil and were formulated according to NRC (2007) recommendations to lactating goats with production of 2 kg⁻¹·goat⁻¹·day⁻¹ and 4% milk fat. Animals were fed twice a day immediately after milking, at 8:00 and 16:00 h. The data were submitted to ANOVA and regression, using the MIXED model procedure from the statistics program SAS 9.1.2. The dry matter intake was reduced linearly (Y = −0.16x + 2.1, r² = 0.914) by the addition of buriti oil (P < 0.05). The milk production and milk production corrected for 4% of fat were not affected by the addition of buriti oil, but the corrected milk production of total solids (Y = 0.033x + 1.152, r² = 0.898) were increased linearly (P = 0.0378). In regards to milk constituents, the fat milk (Y = 0.237x + 4.465, r² = 0.985) was increased linearly (P < 0.0001) by the buriti oil levels in the total diet. The mean concentrations of total protein (37.63 g·day⁻¹) casein (31.80 g·day⁻¹) lactose (45.09 g·day⁻¹) and urea (18.74 mg·dL⁻¹) were not affected by the addition of buriti oil in diet (P > 0.05). The inclusion of buriti oil at 45 g·kg⁻¹ in a total mixed ration increases corrected milk production of total solids and milk fat of Anglo-Nubian crossbreed goats.