The objective of this study was to compare the productive impact (kg day(-1) of milk per cow), nutritional and microbiological quality of milk, in a dairy herd when moving from a conventional milking to a robotized one with feeding systems based on grassland. 12-month data were used for each system, which were obtained from the dairy control for conventional milking and from Lely Astronaut A4 milking equipment for robotic milking. The data were subjected to a comparative analysis through the student's t-test. The robotic system showed significantly (p > 0.05) a higher milk (24.18 +/- 2.76 L) and fat (4.12 +/- 0.34 %) production in relation to conventional milking (22.62 +/- 4.16 L and 4.03 +/- 0.39 % fat). On the other hand, the RCS was significantly higher (p > 0.05) in the robotic milking (221.56 +/- 62.96 x 10(3) cells ml(-1)) in relation to the conventional one (213.56 +/- 94.88 x 10(3) cells ml(-1)).