Platinum-based chemotherapeutic agents such as cisplatin, carboplatin, and oxaliplatin are used as adjuvant or neoadjuvant agents in malignancies of the ovary, cervix, lymphoma, head and neck, and breast. Cisplatin is most commonly used until the carboplatin is approved by the Food and Drug Administration (FDA). Cisplatin is not tolerated in many patients due to severe nausea and renal tubular injury. Carboplatin is used in patients where side effects limit the uses of cisplatin. Although carboplatin is least commonly associated with hematuria, we report a case of carboplatin-induced hematuria with obstructive acute kidney injury (AKI). Our patient, a 63-year-old female diagnosed with triple-negative breast carcinoma and postmastectomy, was started on adjuvant chemotherapy, with carboplatin 700 mg and paclitaxel 250 mg. She developed hematuria with ureter obstruction due to clots, resulting in obstructive AKI. The patient continued to have oliguria and worsening symptoms, and thus, the ureter was stented. The patient's renal function returned to the baseline. In this case, we highlight the fact that carboplatin can cause hematuria with ureter obstruction. Adequate hydration before infusing carboplatin as in cisplatin can reduce the complications.