Oxidative stress caused by chronic intermittent hypoxia (CIH) is the hallmark of obstructive sleep apnea (OSA). Among the first line of defense against oxidative stress is the dismutation of superoxide radicals, which in the mitochondria is carried out by manganese superoxide dismutase (SOD2). Our study utilized heterozygous SOD2-/+ mice firstly in CIH model to explore the role of SOD2. we showed that heterozygous deletion of SOD2 markedly deteriorated pulmonary remodeling and increased the oxidative stress, especially promoted the infiltration of macrophages in the lungs of CIH mouse. Moreover, in the intermittent hypoxia (IH) treated RAW264.7 cells, SOD2 knockdown increased the nucleotide-binding domain-like receptor protein 3 (NLRP3) inflammasome activation accompanied with the IL-1? elevation and caspase-1 activity. Additionally, mitochondrial ROS (mtROS) scavenger mito-TEMPO abolished NLRP3 inflammasome activation in IH treated RAW264.7 cells. Collectively, our results supported that SOD2 contributed to the pathogenesis of CIH-induced lung remodeling. Meanwhile, SOD2 knockdown exacerbates oxidative damage through assembly and activation of NLRP3 inflammasome in macrophages. SOD2 may be a novel therapeutic target for CIH-induced pulmonary inflammation and arteriole remodeling.