Abstract: 【Objective】 Different concentrations of exogenous methyl jasmonate (MeJA) were added to the growth process of turnip, and the effects of morphological indexes and antioxidant enzyme activities of turnip seedlings were measured, aiming at providing theoretical reference for the study of its stress resistance mechanism. 【Methods】 The growth and physiological indexes of turnip seedlings were measured after adding MeJA of different concentrations in 1/2MS medium for 7 days. 【Results】 With the increase of MeJA concentrations, the length, dry and fresh weight of turnip seedlings decreased. The activity of SOD increased first and then decreased, the activity of POD, CAT and APX increased gradually, the contents of soluble sugar, soluble protein and proline, MDA, H₂O₂ and O₂·^- increased gradually, and the content of chlorophyll decreased gradually. 【Conclusion】 The above results showed that exogenous MeJA increased the antioxidant enzyme activity of turnip seedlings, but decreased the growth index of turnip seedlings and inhibited the growth of turnip seedlings.