Objective The objective was to characterize clinical manifestation and imaging findings of solitary plasmacytoma in pelvic bones. Methods Clinical and imaging data for solitary plasmacytoma of pelvic bones in 18 patients were reviewed retrospectively. Conventional radiographs (n=16), computed tomographic images (n=7), and magnetic resonance images (n=14) were reviewed. All the patients were stained with hematoxylineosin and microscopically examined. Results There were eight female and 10 male patients with an age range of 44 to 79 years (average age, 60.1 years). 16 cases showed the cortical disruption with soft tissue mass,the other two cases showed expansive destruction of bone.10 cases showed the cortical disruption with rim osteosclerosis and bony septations. All the cases that had MRI examination showed normal marrow being replaced by tumors and 10 cases had extra-osseous soft tissue mass. The affected bone marrow and soft tissue mass showed isointensity six cases and slightly hyperintensity eight cases relative to muscles. T2-weighted MR images revealed hyperintensity with peritumoral edema. GadoliniumDTPA-enhanced T1-weighted MR images showed significant enhancement in 10 cases. Conclusion Solitary plasmacytoma in pelvic bones is rare, it mainly occurred in elderly patients.Solitary plasmacytoma in pelvis bones have characteristic images that it is important for its diagnosis and differential diagnosis.