Curved-surface components are commonly utilized in the aerospace industry due to their unique structural and mechanical properties. However, the irregular shapes of these components pose challenges in accurately calculating ultrasonic propagation delays during array ultrasonic testing, which can impact defect detection precision. This article proposes a novel frequency-domain reverse time migration imaging technique for array ultrasonic testing of curved surface components that eliminates the need for relying on ultrasonic propagation delays. The method involves utilizing the total focusing method to create an image of the curved surface component, followed by threshold segmentation and curve fitting to reconstruct the surface shape and create a two-dimensional acoustic property distribution model. Subsequently, frequency-domain reverse time migration is used to correlate the forward and backward propagation wavefields, resulting in an internal image of the curved surface component. Experimental results on curved samples show that this method successfully enables internal defect imaging of curved-surface components. Compared with the traditional ultrasonic full-focus method, the imaging quality is improved by more than 66% , and the average quantitative error of defects are reduced by more than 37. 04% .