Abstract: Objective To study the expression pattern of Klf4 in human dental pulp and fibroblasts in vitro. Methods Immunofluorescence was used to obtain the expression of Klf4 and Ki67 in human dental pulp and fibroblasts in vitro. Reverse transcriptase-polymerase chain reaction was used to detect the mRNA expression of Klf4 in human dental pulp cells and inducing mineralization on day 14. Results In human dental pulp,the expression of Klf4 was positive in odontoblasts and vascular endothelial cells; in fibroblasts in vitro, the expression of Klf4 was up-regulated in inducing mineralization on day 14. Conclusion Klf4 was specifically expressed in odontoblasts, and it may be correlated with the differentiation of odontoblasts.