Abstract: Spiraea thichocarpa Nakai with poor drought resistance and S. fritschiana Schneid with strong drought resistance were used as experimental materials under different levels of drought treatments. Proteomics technology was used for studying the changes of expressions of proteins related to photosynthesis of two Spiraea species which was on the basic of measuring the changes of photosynthesis. The results show that the photosynthetic capacities of two Spiraea species decreased under drought stress，light compensation point（LCP）and light saturation point（LSP）decreased，but their capacity of using weak light increased，S. fritschiana Schneid with stronger drought resistance showed a better ability of adapting weak light than that of S. thichocarpa Nakai. Twenty kinds of proteins related to photosynthesis involvedin energy metabolism and transport were identified separately under different levels of drought treatments. In S. thichocarpa Nakai，the expressions included the enzymes in Calvin Cycle and photophosphorylation，the most oxygen-evolving complex proteins and the chlorophyll a/b binding proteins of photosystemⅡ showed obvious up and down regulation under drought stress. While in S. fritschiana Schneid，the expressions included the enzymes in Calvin Cycle，the reaction center proteins and electron transport proteins of photosystemⅠ，the chlorophyll a/b binding proteins of photosystemⅡ，the proteins involved in photophosphorylation and oxidative photosphorylation also showed obvious up and down regulation under drought stress. The proteins related to photosynthesis of two Spiraea species were effected under drought stress. In S. thichocarpa Nakai，it was the proteins related to energy metabolism changed significantly. In S. fritschiana Schneid，it was the proteins related to energy transport changed significantly.

Key words: Spiraea, drought stress, photosynthesis, proteins related to photosynthesis, photosynthetic capacity