We report global potential energy surfaces for both the ground ((X) over tilde (1)A') and the excited ((A) over tilde (1)A '') electronic states of HGeBr as well as the transition dipole moment surface between them using an internally contracted multireference configuration interaction method with the Davidson correction and an augmented correlation-consistent polarized valence quadruple-zeta basis set. Vibrational energy levels of HGeBr and DGeBr are calculated on both the ground and the excited electronic states and found in good agreement with the available experimental band origins. In addition, the (A) over tilde (1)A ''-(X) over tilde (1)A' absorption and emission spectra of the two isotopomers were obtained, and an excellent agreement with the available experimental spectra was found.