Radiative lifetimes of HBr+ and DBr+((II1/2)-I-2, upsilon = 0, 1) have been determined using the monitor ion technique in a triple cell ICR spectrometer with Fourier transform detection. The experimental lifetimes corresponding to the vibrational transition upsilon = 1 --> 0 are 10.2+/-1 ms and 56(-11)(+12) ms for HBr+ and DBr+, respectively. The lifetimes calculated by a coupled electron pair approximation (CEPA) method similar to the method used previously for HF+ and HCl+ are 8.8 ms for HBr+ and 35.8 ms for DBr+, in rather good agreement with the experimental results. A comparison with previous experimental and theoretical results on hydrogen halides shows a shortening of the lifetime between the neutrals and the corresponding ions and a lengthening with isotopic substitution (H by D) as well as with substitution of F by Cl or by Br. The lifetimes corresponding to spin-orbit relaxation are very long 852(-282)(+621) ms for HBr+ and 965(-323)(+546) ms for DBr+. They can be considered as equal within the quite large experimental uncertainty on the contribution of collisional deactivation.