Background: Titanium dioxide nanoparticles (TiO2 NPs) are widely used in various commercial and industrial applications, posing potential risks to human body. Lycium barbarum polysaccharide (LBP) is renowned for its antioxidant and anti-inflammatory properties. This study aims to investigate the protective potential of LBP against TiO2 NPs-induced acute toxicity in splenic and pulmonary tissues. Methods: Forty rats were grouped as follows: Group I, the normal control, received daily 0.1% DMSO intraperitoneally (ip) and 0.5 mL PBS orally. Group II received LBP (100 mg/kg/day) by gavage for 14 days. Group III received a single ip injection of TiO2 NPs (972 mg/kg) on the 8th day. Group IV obtained both LBP and TiO2 NPs. Group V was treated with LBP, TiO2 NPs and Zinc protoporphyrin IX (ZnPPIX), the later was injected ip in a dose of 10 mg/kg/day one hour before LBP. Biochemical, histopathological, and immunohistochemical analysis were conducted on splenic and pulmonary tissues of all rats. Results: TiO2 NPs induced congestion, inflammation, macrophage proliferation, pyknosis and significantly increased caspase-3, CD68, NF-κB, TLR4 immunoexpression with upregulation of markers of oxidative stress, inflammation, apoptosis and fibrosis. Pretreatment with LBP mitigated TiO2 NPs-induced tissue damage but enhanced heme oxygenase-1 (HO-1) mRNA expression. Co-administration of ZnPPIX reversed LBP protective impact. Conclusion: LBP demonstrated the ability to alleviate splenic and pulmonary injuries caused by the acute TiO2 NPs toxicity. LBP prevents TLR4/NF-κB mediated injury triggered by TiO2 NPs through HO-1 upregulation. Further research is required to explore the preventative role of LBP against both acute and chronic toxicity brought by nanomaterials in general and TiO2 NPs in particular