Using virtualization technology to integrate resources has become an important mean to improve the resource utilization of current high-performance servers. Thus the reliability of virtualization technology is very crucial to the service quality of high- performance server. However, the driver fault greatly impacts not only the reliability of operating system inside the virtual machine but also the reliability of the servers. In light of issue, this paper presents a driver isolation architecture inside the virtual machine to improve its reliability. It establishes the authorization table by monitoring the memory information which are used by the driver, captures the driver's write operations by setting the write protection of the shadow page table corresponding to the kernel space of the virtual machine, and judges the correctness of write operations of the isolated driver with the authorization table. Currently, the architecture can isolate drivers inside the virtual machine without modifying them. Experimental results show that the architecture can isolate 84.63% injection faults which cause system crashes with the performance loss less than 20%, and therefore effectively improves the reliability of the virtualization environment.