Diarrhea is still a public health problem in developing countries. Climate is one of the contributing factors that may affect the occurrence of diarrhea. This study aimed to determine the relationship between climate, consisted of air temperature, rainfall, and air humidity with the incidence of diarrhea in Tana Toraja District in 2011-2015. The research sample is the number of months in five years from 2011-2015 i.e. 60 months. The univariate analysis showed that average air temperature, rainfall, humidity, and number of diarrhea cases fluctuated up and down each month. Correlation and regression test were used for data analysis. This research showed that there is a significant correlation of air temperature with monthly diarrhea case (p=0,005) and weak relation (r=0,35 /35,7%) and patterned positive, there is significant relation of rainfall with monthly diarrhea case (p=0,000) (r=0.465 /46,5%) and patterned positive, while air moisture per month did not correlate significantly (p=0,268) and very weak relation (r=0,145/14,5%) and patterned positively. The conclusion of this research is climate factor in this case air temperature, and rainfall has a relation with a diarrhea incidence rate in Tana Toraja regency year 2011-2015.