To provide a semiconductor tester for performing a test at a high speed even when the test of a device to be measured is performed over a plurality of pin cards.

This semiconductor tester includes a tester controller for controlling a test sequence, and the plurality of pin cards connected to this tester controller via a control bus, and measures the device to be measured based on a command of the tester controller. The plurality of pin cards have a bus schedule management section for performing bus control via the control bus independently of the control of the tester controller.