Abstract. Pedicularis longiflora is a typical grassland plant located in the alpine habitat in wet meadows or besides streams. This paper addresses the response and adaptation of P. longiflora under heterogeneous environmental conditions at different slope aspects in an alpine wet meadow, eastern Tibetan Plateau. The results show that P. longiflora at the southeast slope benefited more for its development and population maintenance. It also showed a relatively greater leaf biomass. However, P. longiflora invested more biomass to reproductive organs at the southwest slope aspect, where this species has better population continuation. Isometric scaling existed in coupled organ biomasses of P. longiflora which indicated that genetic regulation plays a key role in biomass allocation. P. longiflora allocated more biomass to aboveground parts, vegetative biomass, and non-photosynthetic organs biomass according to tradeoff values, respectively. In addition, both biotic and abiotic factors influenced biomass production of P. longiflora. Thus, soil temperature and interspecies competition in different habitats needs to be clearly understood and paid more attention to for cultivation and better industrialization of this herbal medicinal plant.