Background <p>Response Evaluation Criteria in Solid Tumors (RECIST) and CA-125 criteria are widely used to evaluate disease progression (PD) in ovarian cancer patients undergoing chemotherapy. However, the recurrent patterns and prognostic factors based on CA-125 and RECIST criteria in patients receiving poly (ADP-ribose) polymerase (PARP) inhibitors remains unclear. This study aimed to assess the recurrent patterns based on RECIST and CA-125 criteria, and to analyse prognostic factors in ovarian cancer patients treated with PARP inhibitors.</p> Methods <p>Patients were categorized into two groups based on the status of CA-125 PD within a ± 7-day window: RECIST PD group (no CA-125 PD within 7 days) and CA-125 PD group (CA-125 PD within 7 days). Recurrent patterns and progression-free survival (PFS) following PARPi resistance were analyzed.</p> Results <p>A total of 133 patients were included, with 69 (51.9%) in RECIST PD group and 64 (48.1%) in CA-125 PD group. The concordance between RECIST and CA-125 criteria for diagnosing disease progression was 18.8%(<i>n</i> = 25). Patients in RECIST PD group showed lower rates of lymph nodes progression (20.3% vs. 50.0%, <i>p</i> &lt; 0.001) and multi-sites progression (24.6% vs. 45.3%, <i>p</i> = 0.012). Patients in CA-125 PD group exhibited poorer response to subsequent treatment after PARPi resistance (median PFS: 5.8 vs. 9.3 months, HR = 2.054, <i>p</i> &lt; 0.001). Multivariate analysis showed that factors associated with PFS after PARPi resistance included residual lesions after primary surgery (No vs. Yes, HR = 0.517, <i>p</i> = 0.028), PARPi treatment duration (≤ 6 vs. &gt;6 months, HR = 2.488, <i>p</i> &lt; 0.001), and recurrence criteria (CA-125 vs. RECIST, HR = 2.431, <i>p</i> &lt; 0.001).</p> Conclusions <p>Patients with RECIST PD but without CA-125 PD were less likely to progress in lymph nodes or multiple sites and might achieve better responses to subsequent anti-tumor therapies.</p>