High-spin states of the neutron deficient nucleus Nb-88 have been studied following the reaction Fe-56 (Cl-35, 2pn) Nb-88 at 120 and 123 MeV bombarding energy. Neutron gated and pure gamma gamma-coincidences were measured with a neutron-gamma gamma-coincidence setup; in addition gamma gamma-coincidences were detected with the OSIRIS-cube at the Cologne tandem accelerator. Via the analysis of gamma gamma-coincidence spectra the level scheme of Nb-88 has been extended up to 9.7 MeV excitation energy. About 88 transitions and 40 new levels have been placed in the level scheme. The experimental level energies and branching ratios are compared to predictions of shell model calculations in the restricted (p(1/2), g(9/2)) configuration space.