Abstract: Provided is a storage system and a test method for a testing Peripheral Component Interconnect Express (PCI Express) interface. The storage system of the present invention includes a plurality of DMA memory units storing test data, a data processing unit connected to the plurality of DMA memory units, wherein a predetermined amount of data is transmitted at least once from a first processing (such as an SAS control chip) to the plurality of DMA memory units through a PCI Express interface and the data processing unit, transmission information is generated and recorded during data transmission, and the transmission information is outputted by the data processing unit while data transmission is completed or an interrupt is generated due to an error occurred during data transmission, and a test unit testing the PCI Express interface based on the transmission information outputted by the data processing unit.