The relationship between retinal detachment and posterior lens capsule rupture in pseudophakic patients was studied. Records of patients with pseudophakic retinal detachment who were admitted to Siriraj Hospital from 1992 to 2004 were reviewed. The patients were divided into 2 main groups: 1) The study group (pseudophakic retinal detachment) 79 eyes (78 cases) which was subdivided into group 1a) pseudophakic retinal detachment with intact posterior lens capsule (50 eyes), and group 1b) pseudophakic retinal detachment with ruptured posterior lens capsule (29 eyes); 2) The control group 99 eyes (90 cases) which was subdivided into group 2a) pseudophakic patients with intact posterior lens capsule (83 eyes), and group 2b) pseudophakic patients with ruptured posterior lens capsule (16 eyes). The relationship between pseudophakic retinal detachment and posterior lens capsule rupture was analyzed by Chi-square test, and risk factors were analyzed by multiple logistic regression. Retinal detachment in pseudophakic patients was found more often in males more than in females, and the average age was 57.9 +/- 11.8 years, the retinal detachment was related to posterior lens capsule rupture (p = 0.003). Patients with pseudophakic retinal detachment with a ruptured posterior lens capsule had a risk 5.7 times greater than pseudophakic patients with an intact posterior lens capsule (adjusted Odds ratio = 5.716, 95% CI = 2.118-15.427). The present study showed that posterior lens capsule rupture increased the risk of retinal detachment. Ophthalmologists should be aware of retinal detachment development after YAG capsulotomy, especially in patients who have other risk factors such as myopia, lattice degeneration, retinal break, or previous retinal detachment surgery.