Cobalt and nickel oxide cluster cations, CoxOy+ and NixOy+, are produced by laser vaporization of metal rods in a pulsed nozzle duster source and detected using time-of-flight mass spectrometry. The mass spectra show prominent stoichiometries of x = y for CoxOy+ along with x = y and x = y - 1 for NixOy+. The cluster cations are mass selected and multiphoton photodissociated using the third harmonic (355 nm) of a Nd:YAG laser. Although various channels are observed, photofragmentation exhibits two main forms of dissociation processes in each system. CoxOy+ dissociates preferentially through the loss of O-2 and the formation of cobalt oxide clusters with a 1:1 stoichiometry. The Co4O4+ cluster seems to be particularly stable. NixOy+ fragments reveal a similar loss of O-2, although they are found to favor metal-rich fragments with stoichiometries of NixOx-1. The Ni2O+ fragment is produced from many parent ions. The patterns in fragmentation here are not nearly as strong as those seen for early or mid-period transition-metal oxides studied previously.