Although the meta-analysis results of this study showed that ACE I/D may be related to IPF susceptibility in Chinese Han population, and the D allele of the ACE I/D gene polymorphism is associated with the susceptibility of IPF, more and higher quality large sample case-control studies will be needed to verify this to provide more effective basis for the prevention and treatment of IPF. Here, ACE is linked to idiopathic pulmonary fibrosis.