Abstract: 【Objective】 This test was carried out to understand the tolerance of blueberry to Mn stress in soil in order to provide basic references for blueberry cultivation.【Method】 Potted blueberry cultivars ‘Gardenblue’ and ‘Tifblue’ were irrigated with 0, 1.0, 2.5, 5.0, 10.0 mmol/L Mn²⁺, and six physiological indicators including the generation rate of O^<sup>-_·2, content of hydrogen peroxide(H₂O₂), malondialdehyde(MDA), soluble protein(SP), ascorbic acid(AsA)and glutathione(GSH)in root were determined, the physiological response and tolerance to Mn²⁺ stress were evaluated.【Result】Less than 2.5 mmol/L Mn²⁺ added in soil was innocuous for the growth of blueberry, over 2.5 mmol/L Mn²⁺ added in soil had negative effect on the growth of blueberry. With the increase of Mn²⁺ concentration, significant changes of O^<sup>-_·2 generation rate, H₂O₂ and MDA content, as well as SP, AsA and GSH content in roots appeared at 2.5 mmol/L and more concentrations, of which, these changes of ‘Gardenblue’ were slighter than ‘Tifblue’. It is inferred blueberry has strong tolerance to Mn stress in soil, and the tolerance is based on the alterations of antioxidants such as SP, AsA and GSH. 【Conclusion】Blueberry has a regulating mechanism for Mn stress, which lead to the strong tolerance to Mn with a threshold value of 2.5 mmol/L Mn²⁺ concentration in soil.