To investigate the relaxation process of excited carriers under resonant conditions, time-resolved photoluminescence of the A free exciton has been examined in CuInS2 at a low temperature. At the resonant excitation with the B free exciton energy, the values of the decay-time constant of the fast component decreases to 26 ps compared with that of the non-resonant constant of 53 ps, whereas the slow component does not change. (C) 2003 Elsevier Science B.V. All rights reserved.