We calculate vibrational levels and wave functions for HO2 using the recently reported ab initio potential energy points of Walch and Duchovic [J. Chem. Phys. 94, 7068 (1991)] as fit by Dateo (unpublished). There is intramolecular hydrogen atom transfer when the hydrogen atom tunnels through a T-shaped saddle point separating the two equivalent equilibrium geometries, and correspondingly, the vibrational levels are split. We focus on vibrational levels and wave functions with significant splitting. The first three vibrational levels with splitting greater than 2 cm(-1) are (1,5,0), (0,7,1), and (0,8,0), where v(2) is the O-O-H bend quantum number. We discuss the dynamics of hydrogen atom transfer, in particular, the O-O distances at which hydrogen atom transfer is most probable for these vibrational levels.