The invention provides a scheduling method for multiple processes to preempt hardware key encryption and decryption resources, which comprises the following steps of: 1, starting a file encryption and decryption service, and automatically creating a performance state thread pool; 2, the hardware key waits for submission of encryption and decryption tasks, file encryption and decryption priorities are defined, and the encryption and decryption tasks are carried out according to the priorities; step 3, detecting whether there is a call or recording, pausing the encryption and decryption task, and continuing to submit the task; 4, releasing hardware key resources, and discarding a file which is being encrypted and decrypted; and step 5, after calling or video recording is completed, continuing the file encryption and decryption task. The method has the advantages that it is guaranteed that other tasks can be carried out in the file encryption and decryption process, the file encryption and decryption efficiency is improved, and normal operation of a system is guaranteed; a thread pool is created for a batch processing file encryption and decryption task, and hardware resources are allocated according to task priorities, so that on one hand, memory consumption is reduced, and on the other hand, system resource management is facilitated.