Although post-stroke shoulder pain is a common medical complication among the stroke population, pseudotumor deltoideus which is non-malignant is rarely seen. This case report demonstrates a thorough history, physical examination followed by the relevant investigations are essential when managing a common post-stroke complication. We postulate that pseudotumor deltoideus is likely a pre-existing asymptomatic variant in our patient before the stroke and has presented symptomatically after the stroke due to the associated neurological and musculoskeletal impairments. As post-stroke shoulder pain is associated with unfavourable outcomes, it is important to recognise the underlying causes of post-stroke shoulder pain early and institute prompt appropriate treatment.