MicroRNAs (miRNAs) have been demonstrated to have promoting or inhibiting effects on the tumorigenesis of multiple cancers, including ovarian cancer (OC), by regulating its downstream target genes. In the presented experiment, our aim was to explore the role of miR-543 in OC cell proliferation and invasion. Results of quantitative reverse transcription-polymerase chain reaction (qRT-PCR) and Western blot revealed that miR-543 have lower expression levels, while Twist homolog 1 (TWIST1) was expressed with higher levels in OC tissues and cells. Furthermore, the effects of abnormal miR-543 expression in OC cell proliferation and invasion were detected by CCK-8 and Transwell assay. According to luciferase reporter assay results, TWIST1 was identified as a downstream target of miR-543 in OC, and a negative correlation was observed between TWIST1 and miR-543 expression by Spearman’s correlation analysis in OC tissues. In addition, TWIST1 may reverse the miR-543 suppression effect on OC cell proliferation and invasion. To sum up, miR-543 may promote OC cell proliferation and invasion by targeting TWIST1.Copyright 2020 Biolife Sas. www.biolifesas.org.