Abstract: An open-ended sleeve antenna loaded with a stepped structure and lumped element is designed. The antenna possesses good voltage standing wave ratio (VSWR) bandwidth. The electromagnetic simulation results show that the VSWR of the proposed antenna is less than 2 in the frequency range from 400 MHz to 700 MHz, and the horizontal gain is greater than 0 dBi. The antenna is also fabricated to demonstrate its performance. The experimental results have good agreement with simulation ones.