Abstract: On the surface of AgBr single crystal (only (422)crystalface, d=0.118nm), vacuum-evaporated dye thin film (thickness about 30nm) exhibites uniform amorphous aggregation. The photocurrent of AgBr single crystal is very small. The action spectra of photocurrent between the "sandwich" configuration devices: conductive glass (incident light face)/AgBr single crystal/dye/Ag and Al/Al_2O_3/(incident light face)/dye/Ag are very similar. It can be concluded that the energy band of AgBr bend up nearby the interface of AgBr/dye as the Schottky barrier of the Al/Al_2O_3/dye interface. Because the valence band of AgBr also bend up, it is possible for the free holes to transfer to the top of valence band. This results in the recombination of the free electrons and desensitization. In AgBr single crystal/dye systems, the photoelectrons transfer from dye into AgBr phase for spectral sensitizers, and in reverse for spectral desensitive dyes. The voltampere curve (J-V) of AgBr single crystal/dye indicated that the distribution between lattice and interval ions in AgBr is not in equilibrium.