The invention discloses a determination method of a 
drought stress level of 
greenhouse crops. The method comprises the steps that drought treatments with different degrees are conducted on plants in the 
seedling stage, the 
leaf water potential, the root activity and the 
malondialdehyde content of the plants under the different treatments are determined, parameters under the different treatments are compared, a regression equation of 
crop drought stress indexes is established, the 
drought stress level is determined, and therefore the disaster situation is determined. According to the determination method of the drought 
stress level of the 
greenhouse crops, the root activity is determined through a TTC method, the MDA content is determined through a TBA reaction method, the 
leaf water potential is determined through a WP4-T 
dew-point 
water potential meter, the parameters are optimized and calculated by synthesizing physiological indexes of the crops, and the 
crop drought level is determined. By means of the determination method of the drought 
stress level of the 
greenhouse crops, the sizes of the the 
leaf water potential, the MDA content and the root activity are determined rapidly and accurately, the operational feasibility is high, the determination accuracy is high, the relative error is small, and the accurate calculation of greenhouse 
crop drought stress indexes and determination of the drought level can be met.