Abstract: Objective：To investigate the relationship between posterior staphyloma and choroidal thickness in pathologic myopic eyes. Methods：A total of 129 consecutive patients with pathologic myopia (258 eyes) were retrospectively selected. Patients were classified as posterior staphyloma (80 eyes of 52 patients) and non-posterior staphyloma (154 eyes of 77 patients), according to ultrasonography and fundus examination. Central subfoveal choroidal thickness (CSFCT) was measured by optical coherence tomography using enhanced depth imaging (EDI-OCT) . The relationship between ocular biometric characteristics and posterior staphyloma was further analyzed. Results：Compared with patients without posterior staphyloma, patients with posterior staphyloma were older, had longer axial length, deeper myopia and thinner CSFCT. Moreover, 1∶1 age- and gender-matched case-control subgroup analysis showed that patients had longer axial length and thinner CSFCT (P＜0.001). After adjusting age, axial length, and CSFCT, the risk of posterior staphyloma increased when age (Δ=5 years old, OR ［95%CI］=1.319 ［1.120, 1.554］, P=0.001） or axial length increased （Δ=1 mm, OR ［95%CI］=1.898 ［1.418, 2.541 ］, P＜0.001）; while the risk of posterior staphyloma decreased when CSFCT increased （Δ=50 μm, OR ［95%CI］=0.314 ［0.174, 0.567］, P＜0.001). Among these indexes, the area under the curve (AUC) of CSFCT was the highest (AUC= 0.866, 95%CI 0.821-0.911, P＜0.001). The positive likelihood ratio of CSCF diagnosed posterior staphyloma was 2.718 with 90.0% of sensitivity and 68.8% of specificity, when Youden’s index was the highest (sensitivity, 90.0%; specificity, 68.8%). Conclusions：Comparing to pathologic myopic eyes without posterior staphyloma, posterior staphyloma eyes have longer axial length and thinner CSFCT. The decline of CSFCT is of high value in the diagnosis of posterior scleral staphyloma, but it cannot be used as a specific indicator.