Poly（ADP-ribose）polymerase（PARP）is a kind of DNA damage repair enzyme. PARP inhibitors include Olaparib （AZD2281），Niraparib（MK-4827），Rucaparib，Veliparib（ABT-888），Fluzoparib and Talazoparib （BMN-673），etc. This article reviews the preclinical research on the combined application of PARP inhibitors against tumor by searching the relevant literatures. Through the synthetic lethal mode ，PARP inhibitors have a strong killing effect on tumor cells with homologous recombination repair defects. However ，for tumor cells with intact DNA damage repair function ，PARP inhibitors often need to be combined with radiotherapy or other drugs to play a role. Combined application drugs include antiangiogenic drugs ，heat shock protein 90 inhibitors，cyclin-dependent kinase 12 inhibitors，immune checkpoint inhibitors ，histone deacetylase inhibitors ，etc. The combined application of PARP inhibitors is expected to enhance the efficacy of anti-tumor drugs and achieve the goals of sensitization ， synergism and reversal of drug resistance ，which is worthy of further in-depth research and exploration of new combined treatment schemes.