Abstract: Phased array ultrasonic testing was used to inspect the butt welds of austenitic stainless steel pipes with a wall thickness greater than 10 mm, and the testing results to optimize the phased array ultrasonic testing process were analyzed. Phased array ultrasonic testing was performed on simulated defect specimens of austenitic stainless steel pipe butt welds of 219 mm × 34.93 mm (diameter × wall thickness) using single sided and single sided dual sided scanning schemes, respectively, and the results were compared with those of radiographic testing. Finally, on-site application was conducted. The experimental results showed that phased array ultrasonic testing can detect various types of common defects in austenitic stainless steel pipes, and the factors such as beam coverage and ease of debugging can be comprehensively considered based on the equipment and probes while designing focusing rule parameters independently.