The collision-energy-resolved angular distributions of Penning electrons for individual ionic state of N-2-He*(2(3)S) were measured. The angular distributions showed increasing intensity in the backward (rebounding) directions with respect to initial He*(2(3)S) beam vector because Penning ionization occurs with a collision against repulsive interaction wall followed by the electron emission from 2s orbital of He*. We also analyzed internal angular distribution by means of fitting parameters using classical trajectory calculations for N-2-He*(2(3)S) on the modified interaction potential. These internal angular distributions suggested the electron emission from 2s orbital of He* and they depended on collision energy and electron kinetic energy. (c) 2006 Elsevier B.V. All rights reserved.