The ultrasonic transducer based on lead zirconate titanate (PZT) ceramics has been widely used for nondestructive evaluation (NDE) applications, but it has crucial limitations in the application of highly attenuative materials. Since lead magnesium niobate-lead titanate (PMN-PT) and lead zinc niobate-lead titanate (PZN-PT) single-crystal materials offer higher electromechanical coupling coefficients than PZT ceramics, they can present improved bandwidth and sensitivity. Despite their major drawbacks such as a significantly higher cost and difficulties in manufacturing, PMN-PT and PZN-PT single crystals will be expected to provide new challenges for NDE applications because of their considerably large piezoelectric coefficients. In this work, we compared the performance characteristics of PMN-PT and PZN-PT single-crystal-based ultrasonic transducers for NDE applications. From the results of Krimholtz, Leedom, and Mattaei (KLM) modeling and simulations, the ultrasonic transducers based on PMN-PT and PZN-PT single crystals with 1 MHz center frequency were fabricated. As a conclusion, there were no significant differences in performance characteristics (signal amplitude and bandwidth) between prototype PMN-PT and PZN-PT single-crystal transducers under the same fabrication conditions.