OBJECTIVE: To examine the relation between the presence of penetration or aspiration and the occurrence of the clinical indicators of dysphagia. The presence of penetration or aspiration is closely related to the clinical indicators of dysphagia. It is essential to understand these relationships in order to implement proper diagnosis and treatment of dysphagia. METHODS: Fifty-eight poststroke survivors were divided into two groups: patients with or without penetration or aspiration. Medical records and videofluoroscopic swallowing examinations were reviewed. The occurrence of clinical indicators of dysphagia between two groups was analyzed with Cross Tabulation and the Pearson chi-square test (p<0.05). RESULTS: Poststroke survivors with penetration or aspiration had significantly high occurrences of delayed initiation of the swallow (p=0.04) and reduced hyolaryngeal elevation (p<0.01) than those without penetration or aspiration. CONCLUSION: The results of this study indicate that delayed initiation of the swallow is a strong physiological indicator of penetration or aspiration during the oral stage of swallowing in poststroke survivors. For the pharyngeal stage of swallowing, hyoid and laryngeal elevation is a key event related to occurrence of penetration or aspiration. Clinical indicators should be investigated further to allow appropriate implementation of treatment strategies for stroke survivors.