The emergence of the implementation of the contract work system, makes employees feel insecure about the certainty of their long-term employment. This contract work system is implemented by companies to increase efficiency and responsiveness to market changes. However, this can cause job insecurity. The purpose of this study is to review previous research conducted on the topic of contract or flexible work system practices and job insecurity and another purpose is to analyze the relationship between contract or flexible work system practices and job insecurity. This study is descriptive and empirical data investigations linking contract or flexible work system practices and job insecurity have been conducted to understand the relationship between the two. The implementation of a contract or flexible work system makes employees experience higher levels of stress followed by prolonged anxiety related to their future careers. The implementation of the work system makes these employees have no job security in the long term. There are two suggestions in this research. First, the company must review the work system, taking into account the various impacts experienced by employees. Second, the government must implement a policy or law that can protect the rights of workers whose work system is contractual, such as establishing a work system and providing more appropriate compensation.