This study aimed to evaluate the beneficial roles of quercetin nanoparticles against lung damage induced by Ehrlich ascetic's carcinoma (EAC) model in mice. Quercetin was purified from the ethanolic extract of Euphorbia helioscopia. All the confirmation chemical analysis as TLC and HPLC were performed. The conversion of quercetin to nanoparticles was carried out using poly vinyl alcohol (PVA) method. The in vivo study was carried on 90 albino mice weighed 25-30 g which were divided randomly into 6 groups; where G1 was the control group, G2 was administered with Quercetin, G3 was injected with quercetin nanoparticles, G4 is the EAC groups, G5 was injected with both EAC and quercetin, and G6 included mice injected with both EAC and quercetin nanoparticles. The lung damage and improvement prognosis were evaluated by the estimation of different oxidative stress biomarkers as reduced glutathione, malondialdehyde, superoxide dismutase, and catalase. In addition, some anti-inflammatory parameters as tumor necrosis factor-α and interleukin-6 were measured. The obtained results indicated the excellent therapeutic role of quercetin in general and the greater effect of quercetin nanoparticles in the lung tissue's improvement and recovery against the damage induced by Ehrlich model. The histological and immunohistopatholgical examinations confirmed these results.