PURPOSE: To determine the effects of travoprost 0.004% and latanoprost 0.005% treatment on ocular surface in primary open angle glaucoma (POAG) patients. METHODS: Clinical, observational prospective study, during 6 months on two groups of patients newly diagnosed with POAG. Group I (10 patients) was treated with travoprost 0.004% and group II (10 patients) was treated with latanoprost 0.005%. The groups were homogeneous about age and sex, exclusion criteria being any ocular or general associated pathology Routine ophthalmic examination was performed before and after treatment. At each examination was performed Schirmer 1 test and break up time test. Conjunctival cytology specimen was taken and goblet cells density evaluated. RESULTS: There was statistically significant difference in goblet cell density Schirmer 1 test and BUT test before and after treatment (p<0.05). For the both groups the decrease of IOP was similar (from 23.7+/-1.5 mmHg to 15.4+/-1.7 mmHg in group I and from 24.3+/-1.5 mmHg to 15.8+/-1.7 mmHg in group II). CONCLUSIONS: This study showed that travoprost 0.004% and latanoprost 0.005% treatment can have adverse effects on ocular surface and may give rise to dry eye symptoms.