BACKGROUND: TE was the frequent CNS opportunistic infection in AIDS in the pre-HAART era. It occurred in 10% of the patients or more depending on the geographic origin, in areas where HAART is not used widely and where AIDS patients are not on appropriate anti-parasitic prophylaxis. Cerebral toxoplasmosis in AIDS almost always occurs from recrudescence of previously acquired infection. It usually occurs in patients with CD4 counts less than 100/μL. Most recently the incidence of cerebral toxoplasmosis has further decreased in the HAART era. The clinical profile of Cerebral toxoplasmosis is as similar to other neuro infection, but differs radiologically and treatment response. OBJECTIVES: The present study is taken up with respect to its clinical manifestations, diagnostic features, response to therapy and outcome. METHODS: We carried out a prospective observational study in 30 patients of cerebral toxoplasmosis who were HIV Seropositive, at Bowring & Victoria Hospitals attached to Bangalore Medical College and Research Institute, Bangalore from September 2007 to September 2009. RESULTS: Out of 30 patients studied, the mean age was35.7±9.3 years. Prevalence of TE was more in males (Ratio was 2.01). Headache and altered sensorium were more common presentation 73.3% each. Mean CD4 count was 59.57±5.32 (4:14 cells/μL). 22(73.3%) were positive for serum antitoxoplasma IgG antibodies. Majority of the TE patients 76.7% showed bilateral multiple ring enhancing hypodense lesion, 20% of the patients showed solitary lesions. Among the 30 patients, clinical outcome was good with 18(60%) improved to combination therapy of pyrimethamine plus sulfadiazine for a period of 14±2 days with minimum toxicity and 6 (20%)patients died during the therapy and 6(20%) patients lost follow up. CONCLUSION: TE was the AIDS defining illness in 50% of our patients. In patients with AIDS, TE is usually a presumptive diagnosis. CT scan brain, was found to be the most useful approach to the diagnosis. There was a significant relationship between CD4 counts of less than 100 cells/μL and development of TE in HIV seropositive patients. Seronegativitiy for anti-toxoplasma antibodies, does not rule out TE. Combination of oral pyrimethamine plus sulfadiazine therapy for a period of 14±2 days was effective in TE.