Background: Smoking is a behavioral habit that adversely affects health. In job security employees are very influential in smoking habits with smoking can reduce boredom and drowsiness in work because the nicotine content in cigarettes can disrupt a person's sleep patterns so as to make use always alert and awake. The importance of someone having a level of knowledge to stop smoking to prevent behavior and the effects caused by smoking Research Objectives: This study aims to determine the relationship between the level of knowledge with smoking cessation motivation at UMY security employees. Method: This study uses a type of quantitative research with a correlation research design using a cross-sectional approach. The total population is 51 people. The sample selection was chosen with the Total sampling technique. The instrument of this study was a questionnaire on the level of knowledge and motivation to quit smoking. The statistical analysis used to test the hypothesis is the Spearmen Test. Results: Knowledge level showed a good category of 48 people (94.2%), enough categories of 2 people (3.9%) and categories of less than 1 person (2.0%). Motivation to Quit Smoking in UMY security employees showed a high category of 16 people (31.4%), medium category as many as 30 people (58.8%) and a low category of 5 people (9.8%). The results of the Spearman statistical test obtained a significant value of p = 0.759 (p <0.05). Conclusion: There is no relationship between the level of knowledge with smoking cessation motivation in UMY security employees (p = 0.759).