PURPOSE: To evaluate long-term ocular surface clinical signs and symptoms response to therapy in patients with chronic ocular GVHD. METHODS: Retrospective review and data modeling. We reviewed the records of post-bone marrow transplantation patients who were newly diagnosed with ocular GVHD and initiated therapy, and analyzed changes in symptoms (Ocular Surface Disease Index [OSDI]; Symptom Assessment in Dry Eye [SANDE]) and signs (corneal fluorescein staining [CFS]; Schirmer test). We used a LOESS technique to fit a model in function of data variations and obtain a predictive value of the scores progression over time. RESULTS: The records of 123 patients who were followed-up for over 2 years (up to 62 months) were reviewed. The median baseline scores recorded were: OSDI 52 units, SANDE 62.2 units, CFS 2.0 Oxford units, and Schirmer 4 mm. After six months of follow up, scores improved for OSDI (-18.6 units, p = 0.007), SANDE (23.7 units, p = 0.01), and CFS (-0.7 Oxford units, p < 0.001). Data analysis showed that after a 2-year follow up the three parameters continued to improve: OSDI -13.67 units (27% reduction), SANDE -17.55 units (28%), CFS -1.1 units (54%), but Schirmer test scores progressively worsened -1.2 mm (22%). CONCLUSION: In patients with ocular GVHD symptoms and corneal fluorescein staining improved after initiation of treatment, meanwhile Schirmer scores declined progressively. This indicates that appropriate treatment in chronic ocular GVHD can lead to mid- and long-term improvements in symptoms and corneal epitheliopathy; however, sustained reduction in Schirmer test scores suggests chronic tear production impairment.