The prevalence of hemiplegic shoulder pain is approximately 22%-23% in the general population of stroke survivors and approximately 54%-55% among stroke patients in rehabilitation settings. Hemiplegic shoulder pain causes a reduced quality-of-life, poor functional recovery, depression, disturbed sleep, and prolonged hospitalization. Herein, we attempted to understand, based on a literature review and experts' opinion, the pathologic processes underlying hemiplegic shoulder pain and the major associated factors contributing to its development. The systematization of underlying pathologies was proposed, which might eventually enable a more constructive clinical approach in evaluating and treating patients with hemiplegic shoulder pain.