〔Abstract〕 To explore the role of leukemia inhibitory factor (LIF) in dental pulp inflammation . Meth- ods Human dental pulp stem cells (hDPSCs) were cultured in vitro as the target cells , the inflammatory response was induced by lipopolysaccharide (LPS) , and high-throughput sequencing was used to detect relevant highly ex- pressed genes in the inflammatory state . The expression of LIF under graded concentrations of LPS stimulation was detected by real-time fluorescence quantitative PCR (qPCR) . The expression levels of interleukin-6 (IL-6) , inter- leukin-1β(IL-1β) , and tumor necrosis factor-α(TNF-α) were detected after LIF knockdown and overexpression in hDPSCs by qPCR . Normal and inflammatory pulp tissues were collected , and the expression of LIF in both tis- sues was detected by qPCR and immunofluorescence (IF) . Results The expression level of LIF increased in hu- man dental pulp cells after LPS stimulation . The expression level of LIF was subsequently elevated in inflammatory pulp induced by graded concentrations of LPS . The expression of IL-6 , IL-1β, and TNF-αwas significantly down- regulated in hDPSCs after LIF knockdown in response to LPS stimulation , while LIF overexpression upregulated the expression of these cytokines . qPCR and IF assays showed high expression of LIF in inflamed pulp tissue . Conclu- sion LIF is involved in dental pulp inflammation and promotes the development of pulpitis .