In the title compound, C14H11BrN2O2, the mean planes of the two benzene rings are almost parallel to each other, making a dihedral angle of 4.09 (1)°. An intra­molecular O—H⋯N hydrogen bond occurs. In the crystal, inter­molecular O—H⋯N and C—H⋯O hydrogen bonds link the mol­ecules into a chain-like supra­molecular structure.

In the mol­ecule of the title compound, C19H19N3O2, the central pyrazole ring makes dihedral angles of 9.89 (3) and 66.06 (5)° with the two phenyl rings, and the two phenyl rings form an angle of 74.05 (5)°. An intra­molecular C—H⋯O hydrogen bond forms a six-membered ring, producing an S(6) ring motif. In the crystal structure, inter­molecular N—H⋯O and C—H⋯O hydrogen bonds link each mol­ecule to two others, forming an infinite one-dimensional supra­molecular structure along the c axis.