This study aims to determine (1) whether motivation has an influence on employee work discipline. (2) whether there is an influence of communication on employee work discipline. (3) whether or not there is an influence of supervision on employee work discipline. (4) whether there is an influence of motivation, communication, and supervision on employee work discipline. This study uses a quantitative approach with the correlation method. The population of this study was made up of employees of PT. Port Pelabuhan Indonesia III (Persero) Tanjung Emas Semarang Branch. Samples were taken using a simple random sampling technique from as many as 104 respondents. Methods of data collection using the questionnaire method. The results of this study are as follows: (1) there is a positive and significant effect of motivation on work discipline with the value of tcount (3,286) > ttable (1,983); (2) there is a positive and significant effect of communication on work discipline with the value of tcount (3,893) > ttable (1,983); (3) there is a positive and significant effect of supervision on work discipline with the value of tcount (3,908) > ttable (1,983); and (4) There is a positive and significant effect of motivation, communication, and supervision together or simultaneously on work discipline with the value of Fcount (58.035) > Ftable (2,70).