An embedded system program code reduction method and system is proposed, which is designed for use to scale down the total amount of program code that is to be burned into an embedded system for the purpose of reducing the embedded system's memory requirement and thereby increasing the embedded system's performance. The proposed method and system is characterized by that the program code loaded into the embedded system only includes bytecode-based application programs (rather than source code based application programs), those essential objects that are required by these application programs during runtime, and the runtime environment from the virtual machine, while excluding the complier of the virtual machine. This feature allows the embedded system to have a reduced memory requirement and a higher system performance.