Background: spotting the scope on triple-negative breast cancer (TNBC) as the most aggressive type of breast cancer, with no targeted therapeutic options. TNBC is often characterized by having defects in DNA repair due to defects in BRCA making this cancer a rational target for the synthetic lethality of olaparib, as an inhibitory target agent of the alternative DNA repair pathway (poly ADP-ribose polymerase “PARP" inhibitor). Objectives: the present study aims to evaluate the value of miRNAs-181a/b as potential biomarkers in predicting the response of TNBC to olaparib. Methods: anti-miRNAs-181a/b was transfected into MDA-MB-231 cell line using HiPerFect transfection reagent, the transfected and untransfected cells were subjected to olaparib. The effect of miRNAs-181a/b on MDA-MB-231 treated cells with olaparib was evaluated through the detection of essential proteins involved in apoptosis and cell proliferation including Caspase-8, Bcl-2, and Ki-67. Further, the expression level of ataxia telangiectasia mutated (ATM) was determined as a functional target of miRNAs-181a/b. Results: a significant decrease in Caspase-8 activity, and Bcl-2, but a significant increase in cell survival, cell proliferation, and ATM protein were observed upon suppression of miRNAs-181a/b by their inhibitors followed by treatment with olaparib for TNBC cell line (MDA-MB-231 cells). Conclusions: our data confirmed that miRNA-181a and miRNA-181b play a critical role for detecting the sensitivity of TNBC cells to olaparib. As well as miRNAs-181a/b could be used as a potentially predictive biomarkers for response to olaparib.