The assessment of diaphragmatic function has received increasing attention in recent decades because of successful clinical application of the electrophrenic pacemaker. Knowledge of the normal value of the phrenic nerve conduction latency according to Korean physical characteristics may be helpful when choosing electrophrenic respiration candidates and for evaluation diaphragmatic function postoperatively. Therefore in this study we have put the emphasis on obtaining the mean value of the phrenic nerve conduction latency in 18 healthy Korean adults and have correlated the effect of the intercathodal distance and the height of the subject with the conduction latency. As a result the mean conduction latency for the phrenic nerve was 7.10 msec (SD 0.14) and the mean intercathodal distance was 33.2cm (SD 0.41). Significant positive correlations of intercathodal distance with conduction latency and with subject height were found.