State-specific ion-molecule reactions of H-atom transfer between the HBr and H-2 molecules with HBr+((2)Pi (i),v(+)) were studied in a free jet flow reactor. The selected spin-orbit and vibrational states of the HBr+ ion were prepared by resonance-enhanced multiphoton ionization. All of the reactant and product ions were monitored using a time-of-flight mass spectrometer. Rate coefficients of the HBr+/H-2 reaction vary from < 2x10(-12) cm(3)/s for the lowest spin-orbit-vibrational state to 2.1x10(-11) cm(3)/s for the highest. Rates for the HBr+/HBr reaction are similar to1.5x10(-9) cm(3)/s independent of the internal state of the ion.