Objective To investigate the role of Agtr1a in regulating LPS?induced inflammation after LBP deletion in primary hepatocytes of LBP knockout (Lbp^{-/ -} ) mice. Methods Primary hepatocytes of WT and Lbp^{-/ -} groups were isolated by a two?step perfusion method to establish an inflammation model induced by LPS. Agtr1a expression in Lbp^{-/ -} mouse primary hepatocytes was inhibited by losartan and siRNA. Cells were divided into a control group A (blank control), LPS group A (LPS stimulation), and losartan group (LPS stimulation was applied after 3 h of losartan treatment). Cells were divided into a control group B (blank control), LPS group B (LPS stimulation), negative control group (LPS stimulation was applied after 12 h of si?NC transfection), and interference group (LPS was applied after 12 h of si?agtr1a transfection). Primary hepatocytes in the WT group were divided into a control group (blank control) and LPS group (LPS stimulated). Western Blot was used to confirm knockout of LBP protein in Lbp^{-/ -} mouse primary hepatocytes. Changes in Agtr1a expression in primary hepatocytes of WT and Lbp^{-/ -} mice under LPS stimulation were verified by Western Blot. CCK8 assays, qPCR, and Western Blot were used to investigate the inhibitory effects of losartan and si?agtr1a on inflammation in primary hepatocytes of Lbp^{-/ -} mice. Results LBP protein was completely knocked out in primary liver cells of Lbp^{-/ -} mice. Compared with the wildtype group, Agtr1a expression in primary hepatocytes of Lbp^{-/ -} mice was significantly increased under LPS induction (P< 0?? 001). The cell survival rate of the inhibitor group was significantly increased (P< 0?? 01). Expression of proinflammatory factors in inhibitor and interference groups was significantly decreased (P< 0?? 01). Expression of inflammation?related protein p?ERK was also significantly decreased (P< 0?? 01). Conclusions Upregulation of Agtr1a expression in primary hepatocytes of Lbp^{-/ -} mice after LPS stimulation compensates for the effect of lipopolysaccharide?binding protein to promote inflammation. Inhibition of Agtr1a expression significantly reduces the LPS?induced inflammatory response in primary hepatocytes of Lbp^{-/ -} mice.