Dehydroabietic acid (DHAA) is a specific organic tracer for the pyrolysis of conifer resin. To understand its atmospheric stability, the degradation behavior of particulate DHAA in the presence of hydroxyl radicals (OH) has been investigated under different environmental conditions using a stainless steel reactor with volume to be 30 cm3 in the dark. At 25 °C and 40 % relative humidity (RH), the second-order rate constant (k2) of pure DHAA with OH was measured to be (5.72±0.87)×10-12 cm3•molecules-1•s-1. Furthermore, the influence of temperature, RH and mixing state on the degradation kinetics of DHAA were also investigated. At 40 % RH, k2 of pure DHAA increases with increasing temperature and follows the Arrhenius equation k2=(8.9±1.9)×10-10 exp[(–1508.2±64.2)/T], while RH do not have significant impact on k2 at 25 °C. At 25 °C and 40 % RH, compared to pure DHAA, the corresponding k2 for DHAA decreased to (4.58±0.95)×10-12 cm3•molecules-1•s-1 when mixed with (NH4)2SO4, while the value was (3.30±0.79)×10-12 cm3•molecules-1•s-1 when mixed with soot. The atmospheric lifetime of DHAA varied from 2.3±0.2 to 4.4±0.8 days under different environmental conditions. This study indicates that degradation of DHAA by OH radical is appreciable and a significant error in source apportionment can occur if the contribution of degradation to DHAA concentration is not considered during air mass aging.