Bangladesh is facing the unavoidable challenge of adaptation to climate change. However, very little is known in relation to climate change and health. This article provides information on potential climate change impact on health, magnitude of climate-sensitive diseases, and baseline scenarios of health systems to climate variability and change. A cross-sectional study using multistage cluster sampling framework was conducted in 2012 among 6,720 households of 224 rural villages in seven vulnerable districts of Bangladesh. Information was obtained from head of the households using a pretested, interviewer-administered, structured questionnaire. A total of 6,720 individuals participated in the study with written, informed consent. The majority of the respondents were from the low-income vulnerable group (60% farmers or day labourers) with an average of 30 years’ stay in their locality. Most of them (96%) had faced extreme weather events, 45% of people had become homeless and displaced for a mean duration of 38 days in the past 10 years. Almost all of the respondents (97.8%) believe that health care expenditure increased after the extreme weather events. Mean annual total health care expenditure was 6,555 Bangladeshi Taka (BDT) (1 USD=77 BDT in 2015) and exclusively out of pocket of the respondents. Incidence of dengue was 1.29 (95% CI 0.65–2.56) and malaria 13.86 (95% CI 6.00–32.01) per 1,000 adult population for 12 months preceding the data collection. Incidence of diarrhoea and pneumonia among under-five children of the households for the preceding month was 10.3% (95% CI 9.16–11.66) and 7.3% (95% CI 6.35–8.46), respectively. The findings of this survey indicate that climate change has a potential adverse impact on human health in Bangladesh. The magnitude of malaria, dengue, childhood diarrhoea, and pneumonia was high among the vulnerable communities. Community-based adaptation strategy for health could be beneficial to minimise climate change attributed health burden of Bangladesh.