The cyber-physical system is an emerging technology for computing that involves sensing, controlling, and monitoring the physical components and cyber components. They are used across various fields for the process of optimization and enhancing functionality. These systems actually are the integration of computational processes, physical processes, and networking processes. The combination of these various types of processes actually changes the way in which security to the system can be provided. The cyber-physical system suffers from various kind of vulnerabilities; they cannot be protected only through the use of cybersecurity techniques and physical security methods. The physical attacks may affect system performance and cyberattacks can leak your confidential information from the system. Security and privacy are the key issues for the CPSs (cyber-physical systems), their development and the way in which they operate. In this chapter, we have discussed the various security and privacy issues and how these issues are different specifically for CPSs as compared to other systems. The various issues and challenges related to privacy and security approaches have also been discussed in this chapter. The main focus of writing this chapter is to help the beginners working in the field of the cyber-physical system to deal with the security and privacy issues and how they can overcome these issues related to CPSs.