An internal mobile antenna operating in LTE full band (698 806 MHz), DCN and US-PCS (1850 1990 MHz) is proposed. To attain the wide bandwidth of low frequency from 700 MHz frequency band, the monopole structure is used to configure the intenna instead of using PIFA. Due to the restriction of the PCB and antenna carrier size, the changed monopole patch inserting a parasitic element in a slit to make the electrical length longer and the current flow aligned to the same direction is applied to satisfy the bandwidth of LTE frequency band. The antenna was fabricated and its measured results of return loss and radiation patterns at each frequency bands are presented. FR4 substrate with relative permittivity of 4.4 was used. The overall size of the proposed antenna is 40 × 100 × 5 mm3.