Degenerate four-wave mixing (DFWM) has two advantages for the study of photoinduced processes when compared to usual holographic recording by two waves: (1) a signal beam shutter is not necessary; (2) a higher signal-to-noise ratio at the photodetector site is possible. Focusing of the recording beams makes it possible to significantly increase the light intensity thus widening the limits of experimental possibilities. In this paper DFWM by focused He–Ne laser 633 nm beams has been experimentally studied in a-As2S3 and azobenzene oligomer (ABO) [4-((4-nitrophenyl)diazenyl)-N,N-bis(2-(tetrahydro-2H-pyran-2-yloxy)ethyl)benzenamine] films in comparison with unfocused DFWM. Experiments show that growing of chromophore concentration increases the DFWM efficiency in ABO. Focusing significantly increases the DFWM efficiency in a-As2S3 but not in ABO. The DFWM efficiency increase in a-As2S3 films can be explained by photothermally stimulated relaxational structural changes. On the contrary, in ABO films the recording is based on the photoorientation of chromophores, and this process is, most probably, hindered by photoinduced heating. The possibility of a precise real-time DFWM with focused laser beams is discussed.