It was studded the relationship between the duration of the service-period, milk production and the reproductive capacity of Holstein cows of Dutch origin. The length of service-period has a negative effect on both milk productivity and reproductive indicators (CI, duration of lactation and RCC). Regardless of the level of milk productivity on normal lactation in cows with a service-period of 101 - 120 days, the average daily production decreases by 3.7 - 4.6% compared when it is less than 100 days. For cows with a service-period of at least 200 days, the average daily production decreases by 15.3 - 19.2%. In the cows with a service-period of 101 - 120 days the milk losses were 244 - 488 kg, compared to those who had the service-period up to 100 days, their increase from 121 to 160 days the milk production damaged by 488 - 854 kg milk, when it was in the limit 161 - 200 days the milk losses constituted 488 - 1447 kg, at exceeding the duration of 201 days the damage caused ranged from 1189 to 2013 kg of milk / lactation per cow. The relationship between the level of milk productivity and the duration of the service period, although positive, is very weak, while between the service-period and the average amount of milk per productive day there is a strong negative correlation.