A computer worm curing system includes a string receiving module, a string generating module and a string replying module. The string receiving module receives an infected string, which is generated by a computer worm, from an infected host, which is infected by the computer worm, through a network. The infected string includes a shellcode, and the shellcode is executed utilizing a vulnerable process. The string generating module generates a curing code for curing the computer worm, and replaces the shellcode in the infected string with the curing code to generate a curing string, such that the curing string can be executed utilizing the vulnerable process. The string replying module replies the curing string to the infected host, such that the curing code of the curing string can be executed utilizing the vulnerable process of the infected host to cure the infected host of the computer worm.