The imidazopyridine fused ring in the title compound, C(20)H(16)BrN(3)O·H(2)O, is coplanar with the aromatic ring at the 2-position [dihedral angle = 5.2 (1)°]. In the five-membered imidazo portion, the C-N bond whose C atom is also connected to the pyridine N atom has predominantly double-bond character [1.334 (2) Å] whereas the C-N bond whose atom is connected to the pyridine C atom has predominantly single-bond character [1.371 (2) Å]. The water mol-ecule engages in hydrogen bonding with the latter N atom; it is also connected to a symmetry-related water mol-ecule, generating a linear chain structure.