Industrial Personal Computer(IPC) system generally works in long duration,and so a stable software is essential for an IPC system.Linux has a good deal advantages,such as,stability in use,open source code and free of charge, therefore an IPC measurement and control system has developed based on Linux. Multi-task scheduling is the critical part in system software.A simple method to realize multi-task scheduling in IPC measurement and control system based on Linux alarm clock mechanism is presented. Linux alarm clock mechanism is implemented by the cooperation of software timers and system call that is used to install and handle alarm clock.First, Linux process timers,soft interrupt signals, relevant system call are introduced,as well as applications of Linux alarm clock mechanism in multi-task scheduling. And then an example of the application in the IPC measurement and control system is given. The system has passed longtime run test,accomplished expected functions and shown well stability, so that practicability of the scheduling method has been authenticated.