Abstract: A method for installing an operating system in a computer includes: enabling the computer to execute a bootstrapping program; enabling the computer to configure a storage device thereof with a system partition and an operating partition, and to make a backup of the bootstrapping program and an operating system loading program in the system partition; and enabling rebooting of the computer through the bootstrapping program, and subsequently enabling the computer to execute the operating system loading program for loading an operating system program to the operating partition, and to set the system partition as a hidden partition. When integrity of the operating system program in the operating partition has been compromised, the computer can be rebooted through the bootstrapping program in the system partition, and the operating system program in the system partition can be executed so as to reload the operating system program to the operating partition.