Abstract: The leaf characteristics and microstructure of chloroplast of peach in solar greenhouse were studied. The result showed that as the light is weaker, the total chlorophyll content，chlorophyll a and chlorophyll b content increased; at the same time, the ratio of chlorophyll a and chlorophyll b decreased. The chlorophyll content of the young leaves is higher than those younger and older ones whether that is under shade condition or under natural condition. The chlorophyll content of NJN is highest among those different peach breed. With the shade degree aggravated, the number of chloroplast per cell in palisesade tissue increased, and the grana lamella is thicker; the amyloid number of younger leaves augmented, while it is reversed in young leaves. As for NJN, the grana number of younger leaves in sponge tissue was cut down when shaded, but there is little difference of the grana number of younger leaves in sponge tissue between Maixiang and Qingfeng. When shaded, the length of the cell in palisesade tissue was shorter compare with those under nature light.

Key words: weak light, peach, leaf, ultrastructure