Climate change in Indonesia in the next medium-term will become a serious threat to food security. A survey was carried out in lowland and highland vegetable production centers of South Sulawesi (covering three season patterns: west, transition, and east) in June-August 2012. In each eco-system, 110 respondents were randomly selected and in total 220 respondents participated in the survey. Data were gathered through interviews by using a structured questionnaire. The study was aimed at assessing actual adaptation to climate change at the farmers' level and identifying constraining factors to the adoption of adaptation options. Results shows that 30 out of 36 listed options, such as conserving the use of water, the use of pest/disease resistant varieties, etc., are potential/relevant adaptation options as perceived by most respondents. Meanwhile, in different season pattern, farmers' perceptions vary regarding for instance the use of cover crop, the use of varieties tolerant to salinity, etc. Most farmers in all season patterns claim that they have implemented some adaptation options, such as planting early in the beginning of rainy season, the use of crop rotation system, etc. However, farmers' perceptions vary regarding the use of cover crop, the use of varieties tolerant to salinity, etc. Majority of respondents perceive the need of technological supports for some options, such as the use of minimum tillage, the use of natural or biopesticide, etc. In the meantime, among different season patterns, farmers' perceptions vary regarding the option of looking for complete climate change information, looking for off-farm part-time jobs, etc. Farmers' perceptions that vary are actually reflecting their response to different farm location specifity. Further analysis suggests that respondents' education, age, and land size significantly affect farmers' decision whether implementing a particular adaptation option or not. Three attitude factors that also show significant influence are attitude towards impact on decreasing quality of life, attitude towards the need for more attention to climate change, and attitude towards farmers' adaptive capacity. Based on rank of importance, the three main contraints of adaptation are low attention and weak government policies regarding climate change problems, expensive price of production inputs and unavailability of specific technologies designed to adapt to climate change. Informative and educational campaign should be continuously carried out to develop climate risk management strategy and improve farmers' skill and knowledge to better coping with climate variability and climate change.