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Tundra is one of the most sensitive biomes to climate warming. Understanding plant eco-physiological responses to warming is critical because these traits can give feedback on the effects of climate-warming on tundra ecosystem. We used open-top chambers following the criteria of the International Tundra Experiment to passively warm air and soil temperatures year round in alpine tundra. Leaf size, photosynthesis and anatomy of three dominant species were investigated during the growing seasons after 7 years of continuous warming. Warming increased the maximal light-saturated photosynthetic rate (<i>P</i>_max) by 43.6% for <i>Dryas. octopetala</i> var. <i>asiatica</i> and by 26.7% for <i>Rhododendron confertissimum</i> across the whole growing season, while warming did not significantly affect the <i>P</i>_max of <i>V. uliginosum</i>. The leaf size of <i>Dr. octopetala</i> var. <i>asiatica</i> and <i>Rh. confertissimum</i> was increased by warming. No marked effects of warming on anatomical traits of <i>Dr. octopetala</i> var. <i>asiatica</i> were observed. Warming decreased the leaf thickness of <i>Rh. confertissimum</i> and <i>Vaccinium uliginosum</i>. This study highlights the species-specific responses to climate warming. Our results imply that <i>Dr. octopetala</i> var. <i>asiatica</i> could be more dominant because it, mainly in terms of leaf photosynthetic capacity and size, seems to have advantages over the other two species in a warming world.