The authors report six cases of glandular lesions made up of endocervical type glands in the urinary bladders of women aged 34 to 65 years (mean, 39 years). Two patients presented with dysuria, one with painless hematuria, one with complaints of pelvic discomfort and hematuria, and one with vaginal discharge. The sixth patient was asymptomatic, but on a routine gynecologic examination, a pelvic mass was found. On physical examination, three women had masses between the bladder and uterus. Four lesions were located in the posterior wall of the urinary bladder, one in the dome, and one in the trigone. Four patients underwent biopsy of the bladder lesion. One of these patients had undergone a hysterectomy 10 years earlier. One woman with a pelvic mass between the bladder and uterus underwent a hysterectomy, bilateral salpingo-oophorectomy, and partial cystectomy. The sixth patient had a transurethral resection of the bladder tumor and left oophorectomy. Histologically, all cases showed intermediate to large-sized irregularly shaped endocervical type glands in the muscularis propria of the urinary bladder. Some glands exhibited cystic dilatation and contained mucinous secretions. The glands elicited no desmoplastic tissue reaction. The intraluminal mucin frequently contained polymorphonuclear leukocytes. In all cases, the glands were lined by mucinous, tall, columnar cells and less commonly by flattened to cuboidal cells. Rare admixed ciliated cells were also observed. The lining epithelium was bland in five cases, but moderate nuclear atypia was seen in one case. Mitoses were not observed in any case. Associated lesions included endometrial type glands surrounded by elastotic stroma in one case, exuberant cystitis glandularis in one case, and a pseudodiverticulum of the bladder in one case. Review of the slides from the patient who had had a hysterectomy 10 years previously revealed endocervical adenocarcinoma in situ. Follow-up (mean = 30 months; range = 6 to 60 months) shows that all patients are alive and well, suggesting that the lesion is benign.