The current study was designed to improve milk production and milk fat percentage by supplemented with black cumin and domperidone for thirteen weeks during lactation in indigenous cows. The experiment was performed in Kaligonjupazila of Lalmonirhat under the department of Physiology and Pharmacology, HSTU, Dinajpur, Bangladesh. At 7 days of lactation 16 deshi cows were randomly divided into 4 groups (n=4 lactating cows in each group). Group T₁ was kept as control, Group T₂ was treated with domperidone (Motigut^®) orally at a dose of 100 mg /day per cow, Group T₃ was treated with Black Cumin Seed Powder (BCSP) at a dose of 80 g orally per cow per day and Group T₄ was treated with combination of domperidone with Black Cumin Seed Powder (BCSP) as above mentioned doses. All the animals were dewormed and vaccinated at initial stage. Over the course of the trial, observations were recorded for milk production and fat percentage in milk. Milk production were increased significantly (P<0.05) in all treated groups compared to the control group and highest was recorded in combined domperidone with Black Cumin Seed Powder (BCSP) group (Group T₄). Production level increased significantly (p<0.05) in all treated groups and highest was recorded in cows of group T₄. The present study reveals that additional supplementation with domperidone plus Black Cumin Seed Powder (BCSP) in feed of lactating cows should better performance over other groups in respect to increase milk production and fat percentage in milk without any health hazard in indigenous cows. This technology may be transferred to farmers since drug (Domperidone) and supplement (BCSP) is available and require minimum stillness.