Kondisi politik dan ekonomi Indonesia yang terus berubah menciptakan tekanan-tekanan dalam bidang ekonomi dan menuntut suatu organisasi untuk melalarkan perubahan struktur organisasi dan sistem manajemen untuk dapat terus bertahan dan berkembang, yang salah satunya dalam bidang ketenagakerjaan. Akibatnya, tercipta job insecurity di dalam setiap tenaga kerja, yang kernudian mempengaruhi work-related behaviour-nya. Metode kuantitatif digunakan sebagai metode penelitian, yang mana menggunakan karyawan departemen produksi PT. X, yang berlokasi di Mojokerto, Jawa Timur, sebagai objek penelitian ini. Menurut hasil penelitian yang telah dilakukan, bahwa job insecurity mempengaruhi work-related behaviour karyawan, yang mana berpengaruh secara positif dan signifikan pada karyawan tetap dan sementara dalam melakukan counterproductive work behaviour, serta berpengaruh negatif dalam melakukan organizational citizenship behaviour. Selain itu, perbedaan tin$at job insecurity pada tiap jenis karyawan tidak signifikan / The Indonesian politic and economic conditions are constantly changing, creating pressures in the economy and requiring the organization to make changes to the organizational structure and management system, which one is in the field of employment, to be able to survive and develope. As a result, created job insecurity in every worker, which then affects their work-related behaviour. The quantitative method is used as the research method, which used production departrnent employees of PT. X, which is located in Mojokerto, East Java, as the object of this study. The result of the research that has been done stated that job insecurity afl-ects employee in work-related behavior, which is a positive and significant effect on the permanent and tonporary ernployees in doing counterproductive work behavior, as well as the negative effect in perlorming organizational citizenship behavior. ln addition, differences job insecurity level on each type of ernployee are not significant