Aspiration is well recognized as a cause of pulmonary disease and is not uncommon in patients with altered consciousness.The mortality rate of aspiration pneumonia is approximately 1% in outpatient setting and upto 25% in those requiring hospitalization. This study was done to see the pattern of pulmonary involvement and outcome of aspiration pneumonia in patients with altered consciousness admitted in medicine department of a tertiary care hospital in our country. This was a prospective observational study conducted among the 52 adult patients of aspiration pneumonia with altered consciousness admitted in the medicine department of Dhaka Medical College Hospital (DMCH), during June 2010 to December 2010. Aspiration pneumonia was confirmed by clinical examination and laboratory investigations. Hematologic measurements (TC of WBC, Hb%, ESR, platelet count), chest X-ray, blood gas analysis, blood urea, creatinine and random blood sugar, sputum for Gram staining, sputum for culture sensitivity and blood culture were done in all patients.Assessment of altered conscious patient was done by application of the Glasgow Coma Scale. Case record forms with appropriate questionnaire were filled for all patients. The mean±SD age was 57.42±13.63 years with ranged from 25 to 90 years. Out of 52 patients, 37(71.15%) patients were male and 15(28.85%) patients were female. Following aspiration 76.92% patients developed pneumonitis, 13.46% patients developed lung abscess and only 9.62% patients developed ARDS. Most (33) of the patients had opacity in right lower zone and 13 patients had opacity in the left lower zone, 6 patients had opacity in right mid zone. Only 10 patients had opacity in both lower zones. In this study overall mortality rate was 23%. If only one lobe was involved radiologically, mortality was 8.33%. If two or more lobes on one or both sides were involved, mortality was in the range of 25-91%.