The present disclosure provides an ultrasonic transducer unit and a manufacturing method thereof. The ultrasonic transducer unit includes a substrate, a first electrode arranged on the substrate, an insulating layer arranged on the first electrode, a vibrating film arranged on the insulating layer, a closed cavity being between the vibrating film and the insulating layer, and a second electrode arranged on the vibrating film. The vibrating film is made of a photoresist. The ultrasonic transducer unit disclosed by the present disclosure adopts the photoresist as a material of the insulating layer and/or the vibrating film, so that the ultrasonic transducer unit with better performance can be obtained.