The development of precision livestock farming is explained by the need to improve efficiency and productivity of livestock farms to face current economic and structural constraints. A definition of Precision livestock farming is the coordinated use of automatisms, sensors to measure parameters relating to the animals or to the livestock buildings and Information Technologies and Communication (TIC) to exchange, analyze, store and restore this information. However, the introduction of these new technologies on farms modifies the farmers’ work and occupation. This study was based on a literature review. Automatic systems for milking or feeding, coupled with data collection by sensors and their restitution in the form of alarms or synthetic reports, allow reducing working time. They carry out the tasks instead of the farmer, facilitating decision-making and improving work conditions. The information obtained can also reduce the mental workload by indicating the necessary interventions to do, for example to detect calving. However, the adoption of these new technologies creates new tasks such as the maintenance and monitoring of the equipment, learning how to use them, consultation and interpretation of data. The multiplicity of alarms or alerts, sometimes during the night, and the increasing risk of breakdowns in these sophisticated electronic systems can cause stress. The complexity of information to manage and analyse can disorientate farmers and cause mistakes in interpretation and diagnosis. Finally, precision livestock farming could cause a lower investment of farmers in practical know-how of animals (visual location of sick animals or heats, etc.). The impact of precision livestock farming on farmers’ work brings positive aspects and can be attractive for young people, but work consequences can also be sources of failure if they are not adapted to the needs and skills of the farmers.