In 2019, Penolih Village was a village that had not declared the status of Open Defecation Free because there were still 46 family heads who defecated openly. The purpose of this study was to analyze the role of health workers and public knowledge about open defecation behavior. This type of research is quantitative with a case-control approach. The number of samples in this study was 62 people consisting of 31 case groups and 31 control groups who were calculated using the sample formula to test the different hypotheses of Lemeshow proportions. The sampling technique was using a purposive sampling method. The results showed that people's knowledge was not good about open defecation behavior (p-value = 0.009; OR = 8,096) and health workers had less role in preventing open defecation behavior (p-value = 0.0001; OR = 15.351) . The conclusions that have a relationship with the high behavior of defecating in the Penolih Village community are poor knowledge of the community about open defecation and the less supportive role of health workers.