Treating grazing pressure as an undesirable output of livestock grazing in a directional distance function improves understanding of how economic behaviour affects the environment. Field survey data from 193 livestock grazing households combined with remotely sensed net primary productivity (NPP) data on the Qinghai–Tibetan–Plateau was used to develop a directional output‐orientation distance function. The average efficiency of livestock grazing households is 0.817 when incorporating grazing pressure as an undesirable output, which means that households can achieve 18.3% more output and decrease proportional grazing pressure holding all inputs fixed. The relative shadow price of undesirable grazing pressure to good output grazing revenue is estimated to be between 1.795 and 3.986. According to the Morishima elasticity of substitution between inputs, there is a significant complementary relationship between grassland, labour and capital.