A compact multiband internal antenna that is composed of a coupled structure with an inverted-L patch and two step-shape forky strips is designed. The antenna has two operating bandwidths 698~1100 MHz and 1570~2910 MHz to cover LTE/GSM/UMTS. Therefore, the proposed antenna can support current all 2G/3G/4G wireless communication network services. The limited volume of the antenna is only 40 × 12.5 × 5 mm3 which is printed on a same size of FR-4 support (FR-4, ?r=4.4), and the miniaturized size makes it very prospective in various 4G LTE mobile terminals. The design methods, the measured results and the geometry of the proposed antenna is represented in detail.