Quantum kinetic transport under high electric fields is investigated with emphasis on the intracollisional field effect (ICFE) in low-dimensional structures. It is shown that the ICFE in GaAs one-dimensional quantum wires is already significant under moderate electric field strengths (≥ a few hundreds V/cm). This is a marked contrast to the cases in bulk, where the ICFE is expected to be significant under extremely strong electric fields (≥ MV/cm). Employing the Monte Carlo method including the ICFE, the electron drift velocity in quantum wires is shown to be much smaller than that expected from earlier investigations.