【Objective】 We studied the thermal stability and degradation kinetics of proanthocyanidins in blueberry (Vaccinium spp.) juice to provide a reference for optimizing storage conditions and predicting the shelf life of blueberry juice. 【Method】 Changes in proanthocyanidins content in blueberry juice with different pH values were observed at different temperatures under aerobic or nitrogen-filled conditions and the reaction order was judged. Then, the degradation model of proanthocyanidins in blueberry juice was established using the kinetic equation. 【Result】 Under aerobic conditions, the activation energies of degradation reaction of proanthocyanidins in blueberry juice at pH 5.8, 4.6 and 2.2 were 25.34, 18.77 and 16.80 kJ/mol, respectively, and the half-life ranged from 1.91 to 4.58 days. Under nitrogen-filled conditions, the activation energies of degradation reaction of proanthocyanidins in blueberry juice at pH 5.8, 4.6 and 2.2 were 56.70, 26.35 and 19.36 kJ/mol, respectively, and the half-life ranged from 1.90 to 15.79 days. 【Conclusion】 With increase in temperature and decrease in pH value under aerobic or nitrogen-filled conditions, the stability of proanthocyanidins in blueberry juice decreased, while the activation energy and half-life of proanthocyanidins degradation reaction significantly decreased. Nitrogen-filled treatment can improve the stability of proanthocyanidins, and the degradation reactions were consistent with the first-order reaction kinetics model. Through verification experiments, it was found that the kinetic model of proanthocyanidins degradation in blueberry juice was well-fitted with the measured values (R²≥60.25%).