The Buffalo rearing is adopting faster rate in arid region of Rajasthan due to its multifaceted utility for both milk and meat. Despite of better management practice are adopted for buffaloes, they also depend upon grazing and poor quality of fodder to meet out their total dry matter intake. The concept of balanced feed with respect to mineral and vitamins are not aware by farmer’s community. Thus, the alternative low cost balanced feed was adopted in buffaloes under field condition to augment the milk production with optimum reproductive efficiency. MNFB was developed at feed technology unit of CAZRI, as solidified block of wheat bran, guar meal, dolomite, -minerals and vitamins mixture powder, salt, molasses and urea solution. The study evaluated feeding effect of multi-nutrient feed block on milk production and reproduction performances of lactating buffaloes. The Buffaloes under treatment were divided randomly into two groups and assigned to two dietary treatments under village condition. After calving, all the buffaloes in treatment group were dewormed with albendazole 3 gms and feeding of MNFB 2 blocks (2 kgs each)/week for 3 months during March to May. The control group received diet containing bajara (Pearl millet) kuti, dry grasses, crushed cotton and til (sesame) cake. Milk production, peak milk yield were increased highly significant. Fat percentage was significantly increased. All Observations were monitored as per format. In reproductive performances were like sign of oestrus, conception and post partum reproductive complication 90%, 86.6% and 0.06% in treatment group and 70%, 60% and 30% in Control group respectively. It was concluded that MNFB feeding improved milk yield, milk fat, general health status and reproductive performance of buffalos, as it is a good source of protein, energy, and minerals. It is recommended that MNFB should be used as a supplementation in lactating buffaloes when they area fed with low quality fodder in arid and semi arid region.