Rectus sheath hematoma is a collection of blood in the sheath of rectus abdominis muscle due to an injury of one of the epigastric vessels or the muscle itself. It is a rare condition that could be caused by the use of anticoagulant injections. We report a 60-year-old lady who received enoxaparin injection on the lower abdomen. Subsequently, she developed bladder perforation secondary to rectus sheath hematoma and was diagnosed using CT angiography scan. Exploratory laparotomy was performed and bleeding was controlled with bladder wall repair. Patient developed multi-organ failure. Three days later, the patient died. Rectus sheath hematoma is a rare condition and it is often associated with the use of anticoagulant injection. Healthcare providers should be aware of such complication for prevention and early diagnosis.