This study was designed to estimate the chronologic difference of the pharyngeal transit time (PTT) between aspirating hemiplegics and non-aspirating ones, and to find out the most effective tool and the condition (position, diet) in the measurement of PTT, and lastly, to evaluate diagnostic validity of each tool in detection of aspiration. We measured PTT of 36 hemiplegics by videofluoroscopy, scintigraphy and swallowing electromyography. PTT was measured in three kinds of chin position (neutral, chin up, chin down) and two kinds of diet (fluid, soft blend diet), and the presence of aspiration to trachea was monitored through fluoroscopic images. The results were as follows; PTT was longer in aspirating group than non-aspirating group(p<0.05). Videofluoroscopy perfomed with fluid and scintigraphy performed with soft blend diet in chin-neutral position were most effective in the measurement of PTT (p<0.01), and these tools were more sensitive than conventional fluoroscopy in detection of aspiration in hemiplegics (p<0.05).