Method for grading a memory

Disclosed is a method for grading memory modules comprising: a testing step which applies at least one test procedure to test a memory, each test procedure is provided with a reliability test; and a grading step which grades the memory into corresponding grade level according to test results of said at least one test procedure, and each test result includes a reliability test result wherein the reliability test has the following steps in sequence: performing a data-writing operation on the memory, wherein the data-writing operation is an operation that writes data to the memory; stopping electric charging the memory; halting a predetermined time period; electric charging the memory; checking data integrity of the memory; and generating the reliability test result according to the data integrity.