Systemic lupus erythematosus is a systemic autoimmune disease associated with various manifestations. Here, we report a compelling case of a 42-year-old woman who presented with lupus enteritis as a sole manifestation of systemic lupus erythematosus and underwent 18F-FDG PET/CT. The resected bowel segment revealed vasculitis, and subsequent workup revealed positive antinuclear and anti–double-stranded antibody levels, confirming lupus enteritis, thus highlighting the diagnostic role of 18F-FDG PET/CT in reaching the final diagnosis.