This study analyzes the language investment and identity towards company staffs while learning ESP program. It used qualitative methodology. The data was taken from direct and online interview. Direct interview has done by the teacher while the class in being progress. While online interview, the teacher has texted to the students by WhatsApp application in approaching the students. These two ways of analysis are important to achieve deeper answer from the students regarding their language investment and identity during the learning process. Direct and online interview which has done by the teacher revealed the deeper analysis on how the students invest their motivation and also how they construct their identity while ESP material is given to them. The findings of this study showed how the language investment and identity of ESP learners during the class. In language investment, the results presented the students motivation are really high in English learning. Supporting family one of the power of them in understanding English lesson. This is because they argued that this English understanding can be used to teach their children about English. Even they are a mother and wife, they keep on invest their time to prioritize in studying rather than their household chores duty as they believe it will smoothen their workflow since this is the work demand which must be acquired. Meanwhile, in terms of Language identity construction, the students constructed their identity on three points. They are as a mother, learner and also staff. This constructing identity can be seen on how they informed the teacher about some meetings that they had join the class together with the children and while cooking because their home duty should do even they are in learning activity. As a staff is proved from some question which have asked by them to the teacher related to the needs of their job activity.