Considering of milk pricing system in Iran, a deterministic model was used to predict Economic weights of milk production, fat percentage, protein percentage and herd life for maximum Profit, when product input were restricted and variable enterprises costs were used in animal unit. The sensitivity of these coefficients to a 20% change on prices of forage to concentrate, feed costs, non-feed costs, milk base price, milk free-market price, average milk production, fat percentage, protein percentage and herd life were examined, using data simulation and available data from three different dairy herds of Iran. On the basic condition, the Economic weights of milk production, fat percentage, protein and herd life in maximum condition were (745, 581.5, 790.5), (460105, 492630, 161877), (424857, 905336, 488234) and (506.7, -16.2, 571.5) in three herds, respectively. Milk production, fat percentage, protein percentage and herd life had the highest sensitivity to change the average milk production, basic milk spice and herd life. Intake changing in forage to concentrate ration had the lowest effect on Economic weights. Economic weights changes in contrast to changing on production factors in different systems had variable effects. Changing of production factors causes difference on Economic weights of traits and their Economic weights should be estimated for each production system.