We evaluated the risk factors for childhood pneumonia with particular reference to indoor air-pollution associated with solid fuel use for cooking (e.g. coal, wood, dung), using a case-control study in a children's hospital in Calcutta. Cases were 127 children aged 2–35 months of either sex admitted with pneumonia and controls were 135 children attending their immunization clinic. Solid fuel use (odds ratio = 3.97, CI = 2.00–7.88), history of asthma in the child (OR = 5.49, CI = 2.37–12.74), poor economic status indicator (OR = 4.95, CI = 2.38 to 10.28), keeping large animals (OR = 6.03, CI = 1.13–32.27) were associated with high risk of pneumonia after adjusting for confounding (logistic regression analysis). Nearly 80% of people in India use such smoke producing fuel and the population attributable risk would be very high. This finding has important health policy implications. Furthermore, history of asthma is a useful prognostic indicator for early action for prevention of severe pneumonia.