Ovarian cancer (OC) is the gynecologic malignancy with the highest mortality rate (70%), and it is urgent to find out a powerful prognostic marker for OC patients. LncRNAs are recently thought to be oncogenes in various cancers, and its expression levels are validated that can be inhibited by miRNAs. There are several studies indicating that sponging miRNAs will contribute to the tumorigenesis of cancers.,In the present study, bioinformatics analysis is used to explore the potential oncogene and its target miRNAs; QRT-PCR is performed to count the expression level of several genes; Flow cytometric analysis is conducted to assess the apoptosis rate of several cell lines; Western blot assays are used to evaluate the expression levels of several proteins; Cells proliferation, migration and invasion abilities are detected by CCK-8 assay, Wound scratch assay and Transwell invasion assay, respectively. In vivo experiments are performed to assess the influence of LNC01133 on the formation of tumor.,We found LNC01133 was related to poor survival of OC patients, and identified that LNC01133 had significant influence on OC cells' apoptosis, proliferation, migration and invasion abilities. Furthermore, we observed miR-126 could target LNC01133 and decreased the expression level of LNC01133 in OC cells. Therefore, we sponged miR-126 to further study the molecular mechanism of OC tumorigenesis, and found an elevation in proliferation, migration and invasion abilities of OC cells, which suggested that miR-126 could serve as a powerful prognostic marker for OC patients, and had great clinical significance on OC diagnosis and treatment.,We found LNC01133 was an oncogene in OC, which is targeted by miR-126. miR-126 served as a powerful prognostic marker for OC patients because of its ability of promoting OC tumorigenesis after sponging.,IJCEP Copyright © 2018.