Abstract: In order to further understand the effect of salt and alkali stress on the growth of Mesembryanthemum crystallinum in greenhouse, 6 treatments were set as CK, T₁, T₂, T₃, T₄and T₅, respectively, to study the change characteristics of growth index, photosynthetic parameters, antioxidant enzyme activity and quality of Mesembryanthemum crystallinum. The results showed that plant height, stem diameter, leaf length, leaf width, fresh weight and dry weight of Mesembryanthemum crystallinum decreased gradually with the increase of salt and alkali concentration, but there was no significant difference between T₁treatment and control. The net photosynthetic rate, stomatal conductance and transpiration rate decreased gradually with the increase of salt and alkali concentration, and there was no significant difference between T₁and control. The activities of superoxide dismutase（SOD）, peroxidase（POD） and catalase（CAT） firstly increased and then decreased with the increase of salt and alkali concentration, and reached the maximum value in T₃treatment. The results indicated that low concentration of salt and alkali stress had little effect on the growth of Mesembryanthemum crystallinum. When the salt and alkali concentration was less than 300 mmol/L, Mesembryanthemum crystallinum could maintain growth by increasing the activity of antioxidant enzymes, but the photosynthesis was still affected. When the salt and alkali concentration was more than 300 mmol/L, the activity of antioxidant enzymes was decreased, and the growth of Mesembryanthemum crystallinum was greatly affected.