This article proposes a broadband sleeve dipole antenna for use on shipboard fences. The antenna consists of a dipole and a sleeve section, operating within the frequency range of 300MHz to 400MHz. It has a relative bandwidth of 28% and a height of 600mm. The antenna design is divided into three parts: optimizing the size of the upper and lower radiation bodies, optimizing the sleeve width, and designing an appropriate impedance matching network. Experimental results show that the antenna has a standing wave ratio of less than 2, an out of roundness of less than 3dB, and a full band gain of over 3.2dBi, which is consistent with the simulation results. Compared to full wave dipoles, this antenna avoids the impact of out of roundness caused by fences, offers miniaturization, which make it suitable for shipborne fences.