Embodiments of the invention disclose a storage unit test method. The method comprises the following steps of: after a test writing command is received from a main device through a first access interface, driving a second access interface by a processing unit to read first test template data from a test writer and writing the first test template data into a physical block address in a storage unit; and driving the second access interface by the processing unit to read second test template data from the physical block address and outputting the second test template data to a test reader, receiving a test result from the test reader, generating a test message according to the test result and replying the test message to the main device.