A microstrip-fed compact folded dual-band slot antenna with further reduced size is presented. The folded slot antenna just occupies a relative small size about 28 mm * 18 mm * 8 mm (W*L*H) for wireless communication usb dongle application. The antenna works for two bands which are 880 MHz–960 MHz and 1710 MHz–2690 MHz. It can be used as GSM and TD-SCDMA antenna or candidate for MIMO applications. The proposed antenna possesses not only a compact size, but also a balance resonant characteristic that has little surface current on the ground which reduces resonant frequency shifting due to the different ground sizes or the hand and knee effect. The designed compact dual-band antenna has been successfully implemented, and the experimental results are presented and discussed. Good agreement between simulation and testing was achieved.