We demonstrated lasing in localized optical resonances of deterministic aperiodic structures with pseudorandom morphologies. The localized lasing modes in two-dimensional arrays of air nanoholes in GaAs membranes occur at reproducible spatial locations, and their frequencies are only slightly affected by the structural fluctuations in different samples. A numerical study on the resonances of the passive systems and optical imaging of lasing modes enabled us to interpret the observed lasing behavior in terms of distinctive localized resonances in the two-dimensional pseudorandom structures. (C) 2010 American Institute of Physics. [doi:10.1063/1.3519844]