The molecule of the title pyrazole derivative, 3,5-diphenyl-1-(phenylacetyl)-4,5-dihydro-1H-pyrazol, C23H20N2O, is twisted. The compound crystallizes in the monoclinic sp. gr. I2/a with a = 15.3502(13) angstrom, b = 12.7576(8) angstrom, c = 19.625(2) angstrom, = 106.639(7)degrees, and Z = 8. In the compound, the phenyl rings form dihedral angles of 12.01(13)degrees, 80.36(8)degrees, and 86.95(9)degrees with the mean plane of the pyrazole ring (r.m.s. deviation = 0.030 angstrom). The central pyrazole ring, which approximates an envelope conformation, is almost coplanar with one of the phenyl rings. The crystal packing is stabilized by weak intermolecular C-HO hydrogen bonds.