We studied 172 patients for development of ocular graft-versus-host disease (GVHD) after allogeneic stem cell transplantation (allo-SCT) from 2002 to 2009. Ocular GVHD was diagnosed in 60 patients (38%), with 27 (16%) being diagnosed at days 100 and 33 (23%) beyond day 100 for a 2-year cumulative incidence of 35% (95% confidence interval (CI), 28-43). The positive and negative predictive values of a Schirmer I test score (using 5 mm as a cutoff) in predicting ocular GVHD (day 100) were 41 and 82%, respectively. In patients with ocular GVHD beyond day 100, extraocular manifestations of GVHD preceded the development of ocular GVHD in most patients (27 of 33, 81%). Prior acute skin GVHD (odds ratio 2.57, 95% CI 1.17-5.64, P=0.019) and male recipients of female donors (odds ratio 2.57, 95% CI 1.09-6.06, P=0.03) were independent risk factors for ocular GVHD. We recommend comprehensive ocular evaluation rather than a screening Schirmer's test to establish the diagnosis of ocular GVHD. Early diagnosis and preventive strategies in high-risk populations need to be studied in clinical trials to prevent devastating impact on quality of life in patients with prolonged ocular GVHD.