We consider the influence of surface modification by SnO₂-Au nanocomposites on the conductivity response of SnO₂ films to ozone. SnO₂-Au nanocomposites with an Au/Sn ratio ∼1 were synthesized by the Successive Ionic Layer Deposition (SILD) method. The thickness of the Au-SnO₂ nanocomposites deposited on the surface of the SnO₂ films was controlled through a change of the number of deposition cycles. It was established that the indicated modification promotes optimization of sensor parameters. It was shown that sensors with a modified surface had a higher sensitivity to ozone and a shorter recovery time. An explanation of the observed effects is given.