Disclosed is a method for displaying signal strength bars in a wireless terminal device. In the first step, RSSI (Received Signal Strength Indicator) values of the wireless terminal device consecutively collected for a predetermined time T are analyzed, and C/I (Carrier to Interference) ratios consecutively calculated for the predetermined time T are analyzed. In the second step, the number of signal strength bars to be displayed on the wireless terminal device is determined based on the analysis result of the first step. In the third step, the determined number of signal strength bars is displayed on the wireless terminal device. The signal strength bars are displayed in consideration of peripheral interferences around a wireless terminal device, and thus users can see the telephone communication quality or data transfer speed more accurately. In addition, the signal strength bars are displayed based on a predetermined number of C/I ratios and RSSI values consecutively obtained, and thus the instability in the displaying of the signal strength bars can be reduced.