Pulmonary tuberculosis (TB) is an infectious disease caused by the bacterium Mycobacterium Tuberculosis and causes many deaths in Indonesia. Transmission of pulmonary TB is one of them due to negative preventive behavior. The purpose of this study was to determine the relationship between family attitudes and preventive behavior of transmission of pulmonary TB. The research design uses Cross Sectional analytics. The population in this study were all families who accompanied patients with pulmonary TB at the Pulmonary Disease Hospital of Sumberglagah Hospital with a sample of 36 people using Consecutive Sampling. Data collection using a questionnaire. The results of the study showed that the majority of respondents had a positive attitude of 23 respondents (63.9%) and the majority of respondents behaved positively, namely 21 respondents (58.3%). Based on the results of the chi square test obtained ρ value = 0.000 α α = 0.05. These results indicate a relationship between family attitudes and prevention behavior of transmission of pulmonary TB. Attitude is a person’s tendency to carry out a behavior so that the more positive (supportive) family attitudes are, the more positive the family behavior can be in preventing the transmission of pulmonary TB.