Provided are an apparatus and a method of testing a semiconductor device. A horizontal maintaining unit provided inside a test head applies load to a probe card in a direction perpendicular to the probe card to hold the probe card in a horizontal state.Probe needles of the probe card are uniformly placed on a central region of pads of the semiconductor device, thereby providing an apparatus and a method of testing a semiconductor device capable of improving productivity and reducing a yield loss of a test process.