The mol-ecule of the title complex, [Ni(C(30)H(23)O(2)P(2))(OH)], adopts a slightly distorted square-planar geometry around Ni(II) defined by the coordination of the two mutually trans P atoms, the Csp(2) atom of the pincer ligand and the O atom of the hydroxide ligand. The largest distortions from ideal geometry are reflected in the smaller than usual P-Ni-P [163.95 (3)°] and P-Ni-C [82.06 (6)°] angles. The OH ligand does not form intra- or inter-molecular hydrogen bonds.