AIM:To determine the frequency of HIV-related ocular involvement and to describe the characteristics of involvement in a special clinic in Tehran.METHODS:In this cross sectional study,141 patients(125 male and 16 female,282 eyes) of HIV-infected patients with various stages of HIV infection that were referred to Center of behavioral diseases were evaluated during a period of 7 months.Every patient had a complete profile including demographic data,method of HIV transmission,recent CD4 T cell lymphocyte count,serological studies for common sexual or blood-born viruses and toxoplasmosis,history of antiretroviral therapy,and associated systemic disease.RESULTS:A total of 141 patients were evaluated.HIV-related ocular involvement was detected in 15 patients(10.6%),including 3 mycobacterium tuberculosis-related choroiditis,2 cytomegalovirusretinitis,2 retinal toxoplasmosis,2 herpes simplex virus-related lesions,1 HIV-associated retinopathy,1 herpes zoster ophthalmicus,1 undetermined vitritis,and 3 cases of cranial nerve involvement including 2 cases of gaze palsy and 1 case of papilitis.In our study,mean CD4 T cell lymphocyte count was fewer in patients with ocular involvement than in patients without ocular involvement(204.7±123.8 vs 403.7±339.7,P=0.029),but there was no difference in other possible associated factors between two groups.CONCLUSION:Mycobacterium tuberculosis-related choroiditis and neurophthalmic lesions are the most common HIV-related ocular involvements in Tehran that is different from those of recent publications in developed countries.