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In order to reveal the photosynthetic response characteristics and correlation of economic tree species to heavy metal stress in soil, common economic tree species in Beijing (Juglansregia L., Amygdaluspersica L.,Prunussalicina Lindl.) were selected as research objects to study the relative content and correlation of chlorophyll under different heavy metal contents (Cr, As, Cu, Pb) in soil. And the resistance mechanism of three economic tree species to four common heavy metal elements was analyzed. The results showed that in the soil environment with different contents of heavy metals, due to the combined effects of heavy metal stress, the relative contents of chlorophyll in plants were significantly different, which indicated that heavy metals in soil had obvious effects on the growth of plants. According to the calculation results of single factor pollution index method and Nemerow comprehensive pollution index evaluation method, the comprehensive pollution levels of heavy metals As and Cr in the soil of the test orchard were light pollution level and warning level respectively, while Cu and Pb were in safety level. In general, the single factor pollution index and Nemerow comprehensive pollution index were As, Cr, Cu and Pb respectively from large to small. The relative chlorophyll content of three economic tree species from large to small were Prunussalicina Lindl. (25.9±6.5), Amygdaluspersica L. (24.3±7.1) and Juglansregia L. (18.55±4.8). There was a significant negative correlation between the relative content of chlorophyll and the content of heavy metals in four kinds of soils, which indicated that heavy metal stress inhibited the photosynthetic pathway of plants, thus reducing their photosynthetic capacity, and with the increase of stress intensity, the inhibition effect on the relative content of chlorophyll was stronger. Among the three economic tree species, Juglansregia L. had stronger resistance to heavy metal stress, Prunussalicina Lindl. took the second place and Amygdaluspersica L.was poorer.