The aim of this study was to conduct a search for microRNAs (miRNAs) that are significant in fetal lung develop-ment to lay a foundation for further studies in the relevant fields. In this study, histological observation was performed in rats by hematoxylin and eosin (H&E) staining at three time points of fetal lung development [Embryo 21 (E21), E19 and E16, and designated as groups S1, S2 and S3, respectively]. An expression profile for fetal lung development was determined using the latest microarray technology. Furthermore, certain differentially expressed miRNAs were selected for further study by real‑time PCR. In total, 202 differentially expressed miRNAs were identified. Among them, miRNA-126* was selected for further study and validated by real-time PCR due to its higher expression levels in the microarrays. The results revealed that the relative expression of miRNA-126* differentially increased as embyronic development increased (P<0.05), which was consistent with the microarray results. In conclusion, we hypothesize that these newly identified miRNAs (including miRNA-126*) may be important in the physiological mechanisms during fetal lung development. These results may aid future studies of neonatal lung development.