In this paper, an S/C/Ku triple-band (TB) dual-polarization (DP) shared aperture array (SAA) with an approximate frequency ratio of 1:1.8:4.5 is proposed. An S/C dual-band dual-polarized (DBDP) perforated patch antenna is designed as a shared element, and the S-band array consists of S-band-working shared elements. The C-band array interlaces with C-band-working shared element and C-band cross-patches with phase compensation. The Ku band array consists of dual-polarization rectangular dielectric resonator antennas (DRAs) for its small section area and high design freedom. In order to ensure the symmetry of the structure, all the ports adopt a vertical welding structure. A 1 × 3 prototype array is fabricated and measured, showing that the S-, C-, and Ku-bands obtain the bandwidths of 2%, 2.1%, and 1.8%, respectively. The polarization isolation is better than 20 dB in all three bands, while the cross-polarization is lower than -20 dB. The proposed array has the advantages of low cost and high integration; moreover, the proposed array owns excellent potential for expansion to large aperture benefited from its symmetry.