The invention discloses a method for detecting a grouting plumpness of a sleeve along a slurry outlet channel single side by ultrasonic method. The method is characterized in that the end surface of the grouting material, close to one side of the surface of a prefabricated part, in the slurry outlet channel is arranged as an ultrasonic detection surface, the ultrasonic detection surface is provided with a smooth surface and is perpendicular to the slurry outlet channel; the method comprises the following detecting steps that an ultrasonic transducer is arranged on the ultrasonic detection surface, the ultrasonic transducer can simultaneously excite the ultrasonic waves and receive the ultrasonic waves; after the ultrasonic transducer excites the ultrasonic waves, the ultrasonic waves are transmitted to the back side of the prefabricated part along the slurry outlet channel, and when the sleeve is fully grouted, the ultrasonic waves are reflected on the back side of the prefabricated part, when the sleeve is not fully grouted, the ultrasonic waves are scattered at the missing end part of the grouting material, close to one side of the sleeve, in the slurry outlet channel; the ultrasonic transducer receives echo signals of the ultrasonic waves; and the grouting fullness can be judged according to whether obvious echo signals exist in the area range corresponding to the slurry outlet channel. According to the method, whether the sleeve grouting is full or not can be detected in a lossless, fast and effective manner.