Carbon nanotubes(CNT) were synthesized by arc-discharge method. To fabricate CNT sensor, CNT powder was dispersed in $alpha$-Terpinol($C_{10}$ $H_{17}$OH) solution. The CNT films were fabricated by screen printing on the interdigitated Pt/Pd alloy electrode. The microstructure of CNT film were observed by scanning electron microscopy (SEM). In order to investigate the gas sensing characteristics of the film, the CNT film was experimented to measure NH$_3$ response and recovery time. And this sensor shows better reproductibility and faster recovery time than another CNT sensors. We suggest the possibility to utilize a CNT as new sensing materials for environmental monitoring.