Abstract: In this study, a water culture experiment was conducted to investigate the effect of silicon addition on the morphological indicators (radicle, seed germ) and physiological indicators [membrane permeability, malondialdehyde (MDA) level and peroxidase activities] of Glycyrrhiza uralensis seedlings under salt stress. Two NaCl concentrations (100 and 200 mmol/L) and six Si levels (0, 0.4, 0.8, 1.2, 1.6 and 2.0 mmol/L) were set as treatments in the experiment. Potassium silicate (K₂SO₄) was used as the source of Si. The Si addition can effectively increase the length and dry weight of germ and radicle of G. uralensis seedlings under salt stress. Under 100 mmol/L NaCl, the 0.4 mmol/L Si treatment promoted radicle growth the most among all the Si treatments, while under 200 mmol/L NaCl, the 0.8 mmol/L Si treatment promoted radicle growth the most. Exogenous Si addition was also able to increase the peroxidase activity and proline content, and reduce the levels of MDA under salt stress. In conclusion, G. uralensis showed enhanced osmotic stress resistance and reactive oxygen scavenging capacity under salt stress when exogenous Si was added to the culture medium and Si addition alleviated growth suppression of G. uralensis seedlings caused by salt stress.