The photovoltage shows a very complicated behavior and could be considered as a new approach to the investigation of the excess carrier transfer in semi‐insulating (SI) semiconductors. Both time‐resolved short‐circuit (SC) photovoltage and photocurrent at the same energies in the range 1.13–1.49 eV for SI GaAs were measured. The peculiarities of the photovoltage were explained in terms of hole transfer between EL2 deep center and a series of acceptor levels. The influence of the electrons and holes was distinguished, which is known to be impossible via conventional photocurrent measurements. ©1995 American Institute of Physics.