The physical state of the photosphere at the main phase of a two-ribbon solar flare on 3 June 1979 is studied. Semiempirical photospheric models are derived from the inversion. The inferred models revealed that the photosphere remained in a disturbed state for a long time during the main phase of the flare. For the inferred atmospheres, the temperature is higher in the upper photospheric layers and lower in the lower photosphere relative to the quiet-Sun model atmosphere. During the flare the heating penetrated to deeper photospheric layers and the upper ones were cooling. Our comparison of the inferred models with the models for a two-ribbon solar flare on 7 October 1979 shows different height distributions of the temperature at the main phase of flares.