The invention discloses a portable ultrasonic cleaning device, comprising: a housing defining a mounting cavity inside and provided with a working opening in communication with the mounting cavity; an electrical panel disposed in the mounting cavity and provided with a drive circuit and a trigger switch; an ultrasonic transducer connected with the housing and arranged in the mounting cavity, a radiating working head of the ultrasonic transducer extending out of the working opening, the ultrasonic transducer being electrically connected with the drive circuit to generate mechanical resonance under the triggering of the drive circuit; a power supply device disposed in the mounting cavity and electrically connected or disconnected with the drive circuit under the control of the trigger switch; a damping pad disposed between the ultrasonic transducer and the housing. The portable ultrasonic cleaning device according to embodiments of the invention can clean local part of clothes to remove local stain on the clothes, saving water and electricity and providing good cleaning effect, is low in working noise and provides good user experience.