A Universal Serial Bus (USB) testing apparatus includes a Central Processing Unit (CPU); a Southbridge; a Baseboard Management Controller (BMC), connected with the Southbridge via USB. The BMC determines if a test starts or finishes, generates a first instruction of creating a virtual control computer when determining the test starts, creates a control module and a comparing module in a memory unit which are running to become the virtual control computer, and connects the memory unit with the BMC according to the first instruction. The control module sends control data to the CPU. The comparing module obtains feedback data from the CPU and compares the control data with the obtained data to determine if the control data is consistent with the obtained data, thereby determining whether the USB is working normally.