Structures of B2H2n2+ dications (n = 1-4) were investigated at the QCISD(T)/6-311G** level of theory. Thermodynamic and kinetic stabilities of the dications were also estimated. Although deprotonations of the dications are exothermic (except the dication B2H22+), they show considerable kinetic barriers. The charge distributions and Wiberg bond indices were calculated by the NBO method. B-11 NMR chemical shifts were also calculated by GIAO-MP2 and GIAO-DFT methods.