Over the past 20 years, flood and drought in Thailand have impacted up to 2.58 million farming households and caused damages about 6,000 million Baht each year. Various studies have examined natural hazard impacts on the Thai economy and particularly on agricultural sector. Moving towards sustainable development, economic vulnerability to natural hazards should be improved which could be linked to disaster mitigation policies and development. This study aims to explore the Kuznets relationship between economic growth and damages from flood and drought in the Thai agricultural sector using annual data at the provincial levels during 1989-2012. It is hypothesized that as the country becomes wealthier, appropriate development and investment in disaster mitigation could lead to disaster reduction in agricultural sector. Results from the random effect regression support the Kuznets hypothesis in the models for both flood and drought. Precipitation variation increases agricultural damages due to flood and drought significantly. Agricultural damages reduce with rising provincial incomes, increased flood retention area and increased areas for perennial crops.