The carrier transport mechanism of a single-layered photoreceptor containing titanyl phthalocyanine pigment dispersed in an insulating binder polymer was investigated by the measurement of hole drift mobility, using the conventional time-of-flight technique. The transient waveform of the photocurrent exhibited a plateau and kink at higher electric field than 2 × 10⁵ V/cm. The drift mobility for a titanyl phthalocyanine-polycarbonate polymer layer varied from 1.2 × 10⁻⁶ to 7 × 10⁻⁵ cm² V⁻¹ s⁻¹ as the concentrations changed from 20 to 50 wt% of pigment. The increase of dark conductivity and drift mobility in the range of pigment concentration higher than 20 wt% of pigments depended on the formation of pigment particle chains in the photoconductive layer