A bag on the right side of the bladder may be caused by bladder stones, bladder tumors, pelvic tumors and other diseases. 1. Bladder stones: Bladder stones may be associated with concentrated urine or abnormal metabolic levels in the body. If stones are present on the right side of the bladder, it may look like a growth on the bladder when a test is performed. 2. Bladder tumor: the pathogenesis of bladder tumor is not clear, it is considered to have some relationship with genetic factors and improper lifestyle, which will result in poor urination, hematuria, etc. With the gradual increase of tumor will cause a bag on the right side of the bladder. 3. Pelvic tumor: it refers to organic diseases in female’s pelvic cavity, which are commonly caused by ovarian cancer, endometrial tumor, etc. Tumor on the right side of ovary or endometrium near the bladder can be manifested as a bag on the right side of the bladder. In addition, a bag on the right side of the bladder can also be seen in other diseases, which need timely medical treatment according to the cause of the disease.