Purpose: To determine prevalence and associations of incomplete posterior vitreous detachment (PVD). Methods: The population-based cross-sectional Beijing Eye Study 2011 included 3468 individuals with a mean age of 64.6 +/- 9.8 years (range: 50-93 years). A detailed ophthalmic examination was performed including spectral-domain optical coherence tomography (SD-OCT). Incomplete PVD was differentiated into type 1 (shallow PVD with circular perifoveal vitreous attachment), type 2 (PVD reaching fovea but not foveola), type 3 (shallow PVD with pinpoint vitreous attachment at the foveola), and type 4 (PVD completely detached from the macula, attached to the optic disc). Results: An incomplete PVD was detected in 3948 eyes (prevalence: 60.5 +/- 0.6%; 95% Confidence Interval (CD: 59.3%,61.7%) of 2198 subjects (67.1 +/- 0.8%;95%CI: 65.6%,68.7%). Type 1 PVD was seen in 3090 (78.3%) eyes, type 2 PVD in 504 (12.8%) eyes, type 3 PVD in 70 (1.8%) eyes, and type 4 PVD in 284 (7.2%) eyes. Prevalence of incomplete PVD was associated with younger age (P<0.001;OR:0.91), male gender (P<0.001;OR:0.64), rural region of habitation (P<0.001;OR:0.49), larger corneal diameter (P=0.04;OR:0.91), better best corrected visual acuity (P=0.02;OR:0.41), and hyperopic refractive error (P<0.001;OR:1.15). The type of incomplete PVD was associated with higher age (P<0.001), urban region of habitation (P<0.001), myopic refractive error (P=0.001), thinner cornea (P=0.005), and better best corrected visual acuity (P=0.056). Conclusions: In adult Chinese in Greater Beijing, prevalence of an incomplete PVD (detected in 67.1% subjects) was associated with younger age, male gender, rural region of habitation, larger corneal diameter, better best corrected visual acuity and hyperopic refractive error.