In the context of the global climate change,drought disaster may have increasinly serious influence on agriculture industry and food safety. It is significant to conduct drought disaster risk assessment of farm production. Choosing the typical area of northern area of Dongting Lake region as study area,the influence elements of monthly total precipitation,average temperature,total solar radiation and total surface runoff during the paddy rice growing period were selected to build vulnerability relationship with paddy rice output reduction due to drought. Based on historical records,proxy variables of hazard-formative factors of paddy drought were identified,and by Monte Carlo method, drought disaster risk was assessed. The results show that : (1) The proxy variables of hazard-formative factors that contribute evidently to the reduction of paddy rice output are total precipitation in July and August. Every 1.0 mm precipitation decrease will lead to 2. 86% and 3. 34% loss of the paddy rice in July and August respectively ; (2) The annual loss rates of the paddy rice caused by drought disaster for return periods of 5 , 10 ,20 and 50 years are 2. 3%,11. 2%,22. 7% and 50. 3%,respectively.