A behavioral investigation in deer equipped with EMG telemetry system was carried out to examine the chewing behavior pattern for efficient feeding management of Korean spotted deer(Cervus nippon). There was more frequent and irregular eating and rumination behavior pattern in deer than those in other ruminants. Time spent on eating and ruminating was 261 and 291 min., respectively. Total number of boli regurgitated was 647 times per a day and deer regurgitated an average boil of 21.6 times per a rumination period. Total rumination time was 291 min. and deer have an average rumination time of 26.9 sec. per a boli. Deer had 245.3 min. for total chewing time, 20,405 times fur number of chews, 31.5 times for number of chews per bolus, and 53.4 times for number of chews per minute during rumination period. An average regurgitation bolus an hour was lower with 15.3 numbers in the 09∼15 hours subperiod and higher with 26 numbers in the 15∼21 hours subperiod and it had been gradually trended to become to low after 15∼21 hours subperiod. An average numbers of chews a bolus at every 6 hours subperiod increased gradually according to time. A deer spent 23.3 min. on eating and 26.2 min. on ruminating per 100g ingested dry matter. Consequently, since deer have a different chewing behavioral pattern to other ruminants such as more frequent and irregular eating and ruminating patterns, small bolus and low number of chew, it is likely to needed to establishment and development efficient feeding system for deer.