Abstract: Pot and field experiments were conducted to study the influence of application of polyvinyl alcohol(PVA) on the yield and quality and some physiological indexes of oriental tobacco. The results showed that application of PVA the plant height, intercalary distance, and the chlorophll and souble sugar contents were increased in fresh leaves of tobacco, and the photosynthetic rate. nitrate reductase activity and root activity of tobacco were enhanced. PVA could promote earlier growth and mature of tobacco leaf, and improve the rate of middle-high quality leaf,mean price and value of product, but the yield of tobacco leaves was not significantly different as comparied with CK- Meanwhile. the total potassium content increased and sugar pertroleum ether extract and nicotine reduced in the air-dry leaves. In addition, the micro-structure and particle diameter of soil applied PVA were observed by scanning electron microscope(SEM) and micro-optical-density-meter (MODM) indlcating, more micro-aggregates and micropore were found. The particle slze over of 90% was in 9～15 m and only in 4～10 m without PVA treatment.These results indicated, application of PVA can improve the soil structure and crop growing environment. promote growth and enhance quiality of oriental tobacco.