The crossbred cows occupy an important place in milk production system of North-Eastern States (N-E States). In majority of the states except Assam and Tripura, crossbred cows produced more than 50 per cent of the total milk (2007-08). However, milk production from crossbred animals in the region is affected by a number of technical constraints. The present study estimates the value of milk losses due to important constraints in order to quantify the loss and set priorities for their removal. Data for the study were collected from N-E States for crossbred cows. Based on the estimates, mineral deficiency appeared to be the most important constraint causing maximum economic losses, i.e., Rs. 55.28 crores followed by repeat breeding (Rs. 36.62 crores) and worms infestation (Rs. 12.91 crores). These three constraints account for 94 per cent of the total value of milk loss where mineral deficiency alone accounts for approximately 50 per cent losses. While, foot and mouth disease, mastitis, haemorrheric septicaemia, black quarter and milk fever placed in decreasing order in terms of their rank based on economic losses were found to be the minor constraints accounting for only six per cent of the total value of milk loss (Rs. 112.08 crores). All the constraints had lowered milk productivity of crossbred cows by 0.862 L/day. Tackling the constraints will increase milk production of the region by six per cent and will improve milk productivity and generate surpluses.