Abstract: Simulation studies were carried out for ultrasonic phased array inspection of a thin aluminum plate with corrosion pits by using the defect response function of CIVA software. The optimum inspection parameters were obtained by analyzing the relationships between the energy of wave amplitude and the depth of corrosion pit defects with the constant size together, and the size of corrosion pit defects with the specific depth. In combination with the actual ultrasonic phased array detections operated with OmniScanMX, the results obtained by CIVA simulation were consistent with the actual detections, which indicated that CIVA could guide ultrasonic phased array inspection for thin aluminum plate efficiently and accurately.