Objective The transperineal fourdimensional ultrasound stereoscopic imaging combined with mobile technique was used to locately and qualitatively evaluate the diagnostic value of perineal fourdimensional ultrasound in the diagnosis of female periurethral cystic lesions. Methods From November 2017 to December 2018, 2125 female patients who underwent pelvic floor ultrasound examination in Suining central hospital were selected as the study object. GE voluson E8 color ultrasonic diagnostic instrument was used. First, the position, shape and the relationship with urethra and vagina were observed by two-dimensional ultrasound. Then, the abdominal volume probe Rab6 D was used. The fourdimensional imaging was used in the midsagittal plane. Then, the sampling frame was moved up and down to show the spatial position of the cystic lesions around urethra, so as to carry out positioning and qualitative diagnosis.Results Among the 125 cases, 21 cases were found with cystic lesions around the urethra, all of which were confirmed by operation and pathology, including 3 cases of urethral diverticulum, 9 cases of cyst of vaginal wall, 8 cases of cyst of paraurethral gland, and 1 case of abscess of vaginal wall. This case of vaginal wall abscess was misdiagnosed as urethral diverticulum by four-dimensional transvaginal ultrasound, the diagnostic accuracy was 95.2% (20 / 21). The combined diagnosis of transvaginal and transperineal two-dimensional ultrasound showed that there were 7 cases of cyst of vaginal wall, 4 cases of cyst of paraurethral gland and 1 case of diverticulum. There was a significant difference between transvaginal four-dimensional ultrasound and transvaginal two-dimensional ultrasound (P < 0.05).Conclusion Transperineal fourdimensional ultrasound combined with movement technique is of great clinical value in the diagnosis and differential diagnosis of female periurethral cystic lesions.