Background: Idiopathic pulmonary fibrosis (IPF) is a progressive interstitial lung disease with unknown etiology and treatment options for it were limited. Whether Gastroesophageal reflux disease (GERD) could affect the occurrence of IPF remains unclear. Methods : Using available data from FINNGEN and IEU OpenGWAS, we performed Two-sample mendelian randomization (MR) to explore the causal relationship between GERD and IPF. Results: Using 65 GERD-related SNPs, we found the association between GERD and the risk of IPF was not statistically significant with IVW approach (OR = 1.20, 95% CI = 0.84-1.70, p = .32), MR-Egger regression (OR = 1.65, 95% CI = 0.19-14.43, p = .65) and weighted median approaches (OR = 1.44, 95% CI = 0.94-2.23, p = .09). However, heterogeneity was observed with MR-Egger ( p = .001) and IVW ( p = .001) analysis. Similar results were obtained with MR-PRESSO (global heterogeneity test p value