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Porosity and rough surface of EB-PVD (Electron Beam-Physical Vapor Deposition) deposited ZrO2-7%Y2O3 coatings with the thickness of 150 μm on heat-resistant steel have been characterized using the ultrasonic reflection coefficient phase spectrum.High-intensity pulsed ion beam (HIPIB) irradiation at 300 A/cm2 with a shot number of 1,and 5 was performed on the coatings and caused the modification of properties.With increasing the shot number,the surface remelting and ablating filled gaps and caves between columns,and induced more uniform and compact structure.The ultrasonic measurement was investigated using immersion focusing pulse echo method with a 25 MHz transducer.The changing of the phase ultrasonic reflection coefficient related to frequency,velocity and attenuation coefficient were analyzed based on the acoustic transmission model in a multi-layered structure.For the as-deposited coating and coatings irradiated by HIPIB with the shot number of 1 and 5,the ultrasonic velocity increased from 2737 m/s to 3009 m/s and 3200 m/s respectively.