New-built rural residential buildings in Guangdong province have the tendency of multilayer and courtyard disappearance, resulting in the change of the indoor thermal environment. Three typical buildings are selected to measure the parameters of indoor thermal environment in order to understand the status quo of indoor thermal environment in new-built rural residential buildings in Guangdong. It's found that there are several defects count against indoor thermal environment on the basis of comparative analysis. Thus, optimizations were made for design strategies such as shading, insulation and natural ventilation in low-rise buildings with/without patios. There are effective measures to improve the indoor thermal environment in summer of low-rise buildings with patios like the shading roof，increasing height of skylight and skylight placed under the wind direction. Numerical analysis was conducted to quantify the energy and comfort performance of these design strategies. Stilt floor was found to be a good way to build semi-open spaces in low-rise buildings without patios.