Unilateral biportal endoscopy (UBE) surgery is a minimally invasive approach for treatment of spinal disorders, which usually requires creation of a working and viewing channel on 1 side. The UBE technique has developed rapidly in China in recent years, and many spine surgeons have started to apply it and have shared the initial clinical research results many times at minimally invasive spine conferences. Unfortunately, these studies actually translated into fewer publications. In addition, most patients have good outcomes after UBE surgery, but a minority still experience UBE surgery-related complications, including epidural hematoma, dural sac tears, retroperitoneal effusions, inadequate decompression, postoperative back pain and headache, early recurrence, iatrogenic spinal instability, anemia, and infection, which can prolong hospital stay and seriously affect patient satisfaction. Therefore, this article reviews the complications of UBE surgery for lumbar degenerative diseases and discusses ways to prevent and handle complications associated with UBE to help spine surgeons make smart treatment decisions.