Single crystals of Pb(H2PO4)(2) were grown under hydrothermal conditions. X-ray crystallography showed that the title compound crystallizes in the triclinic system with space group and lattice parameters a = 7.812, b = 8.311, c = 5.859 Angstrom, alpha = 108.23 degrees, beta = 96.85 degrees, gamma = 108.62 degrees, Z = 2, and rho(cal) = 4.011 g.cm(-3). The structure was solved from 3705 independent reflections with R = 0.043 (wR = 0.11). It can be regarded as made of independent [PO4] tetrahedra. Two apices of each [PO4] tetrahedron are connected to two H atoms to form [H2PO4](-) anions arranged in a way to delimit large and distorted cavities occupied by lead cations. The resulting arrangement could be seen as made of infinite strips,developing along [001] and connected through hydrogen bonds.