Abstract: By controlling the phase delay of ultrasound，ultrasonic phased array inspection technology achieves beam deflection and focus, then detects internal defects. So the phase delay accuracy is the key to this technology. The FPGA chip has complex and powerful timing functions and meets ultrasonic phased array delay control needs. Through a phase-locked loop frequency multiplier and phase shift, the system adopts synchronization and latency design, and reaches 1 ns delay resolution. Simultaneously, processor achieves parameters reconfiguration function, and those parameters are the delay time and cycle and repetition frequency of the excitation signal. Modelsim software simulation results verify the feasibility and correctness of the design.