In the title compound, [Cu(C(18)H(15)P)(2)(H(2)O)]BF(4), the Cu(I) atom is coordinated by two P atoms from triphenyl-phosphine ligands and one water mol-ecule in a distorted trigonal geometry. In the BF(4) (-) anion, three F atoms are disordered over two sites around the B-F bond, the site-occupancy ratio being 0.67 (6):0.33 (6). The Cu⋯F distance of 2.602 (5) Å between the Cu atom and the ordered F atom may suggest a weak but genuine inter-action. O-H⋯F and weak C-H⋯F hydrogen bonding is present in the crystal structure.