Objective: To investigate the clinical value of serological biomarkers (white blood cell count [WBC], neutrophil/lymphocyte ratio [NLR], prealbumin [PA], platelet distribution width [PDW], mean platelet volume [MPV], CA125,and D-dimer) to diagnose ruptured ovarian endometrioma and construct a prediction model. Design: Case-control study Setting:Single-center Population:Seven hundred and eighty-five women diagnosed with ruptured (n=181) and unruptured ovarian endometrioma (n=604) between January 2011 and December 2021. Methods:The differences in serological biomarkers (WBC, NLR, PA, PDW, MPV, CA125, and D-dimer) between the two groups were analyzed using logistic univariate analysis to select independent variables. Biomarkers with statistically significant differences were included in a logistic multivariate analysis to construct a regression model and thereby predict ruptured ovarian endometrioma. Operating characteristic (ROC) curves were used to evaluate the diagnostic value of the predictive model. Main outcome measures:serological biomarkers (WBC, NLR, PA, PDW, MPV, CA125,and D-dimer in ruptured ovarian endometrioma. Results: Univariate analysis revealed that WBC, NLR, PA, PDW, MPV, CA125,and D-dimer levels were correlated with ovarian endometrioma rupture (P<0.05). The optimal cut-off values were determined using the ROC curves,and multivariate analysis showed that WBC>7.81×109/L, NLR>2.65, PDW>15.55fL,MPV<9.50fL, PA<0.189g/L,CA125>94.63U/mL, and D-dimer>195.5ug/L were independent predictors of ovarian endometrioma rupture. The area under the curve(AUC) of the model was 0.983.The sensitivity and specificity of the predictive model were high (93.4% and 96.4%,respectively). Conclusion:WBC,NLR, PA, PDW, MPV,CA125,and D-dimer can be used to facilitate early identification of ruptured ovarian endometrioma and early intervention. The diagnostic model established in this study is of great importance for diagnosing ruptured endometriotic cysts.