Time-Resolved spectroscopy is a powerful tool for investigation of photogeneration and photoconduction mechanism in layered organic photoreceptors because it can directly detect transient species in each step. So far, we have measured the transient absorption spectra of layered organic photoreceptors using azo pigments as charge generation materials (CGMs). As an extension work of our previous study, we applied this technique to photoreceptors using titanyl phthalocyanines (TiOPcs) as CGMs. For photoreceptors containing TiOPcs and CTMs, we obtained almost the same transient absorption spectrum as we observed in azo-CGM/CTM layers. However, TiOPcs gave weak transient absorption even without CTMs, whereas azo CGMs did not. We also found that the response to external electric field largely depended on the crystalline phase of TiOPc. It is interesting that these results strongly correlate with the photocarrier generation mechanism and the sensitivity of photoreceptors. These experimental results are discussed in connection with photocarrier generation mechanism.