The invention provides a probe apparatus. The apparatus uses the probe card to invest the electrical characteristics of IC chip on wafer to have a compact size and achieve a high throughput. The probe apparatus includes a first and a second loading ports (11, 12) for mounting therein two carriers facing each other, a wafer transfer mechanism (3) having a rotation center between the loading ports (11, 12), and a first and a second inspection units (21A, 21B) being symmetrical to each other and disposed in accordance with the arrangement of the loading ports (11, 12). In this configuration, wafers are directly transferred between the carrier and a wafer chuck (4A) (or (4B)) of the inspection unit (21A (or 21B) by the wafer transfer mechanism (3). The wafer transfer mechanism (3) has three arms for unloading two wafers from the carrier.