The utilization of natural grassland is an important part of grazing animal husbandry. Effective monitoring and accurate estimation of the utilization of natural grassland is an inevitable requirement for the sustainable development of grazing animal husbandry. In order to estimate the utilization process of natural grassland effectively, this paper proposes a grassland utilization estimation method based on environmental sense. In this paper, the distribution of feed intake was obtained by the GPS track data, and the distribution of grassland biomass was obtained by the satellite remote sensing estimation model of natural grassland. The feed intake and grassland biomass are classified and compared respectively. According to the value of the two, the utilization of grassland in each region was obtained. And this study designed a grassland utilization estimating system based on this estimating method and 3S technology. The results show that this method is of great significance to the rational utilization of grassland and the implementation of rotational grazing. The system can provide decision-making basis for ranchers and grassland livestock management departments to manage grazing and grassland. It enables ranchers to make reasonable and effective grazing plans, so as to make balanced utilization of grassland resources and promote the sustainable development of grazing animal husbandry.