Bereg (Rusyn: Береґ; German: Berg) was an administrative county (comitatus) of the Kingdom of Hungary.

Its territory is now mostly in western Ukraine and a smaller part in northeastern Hungary.

The capital of the county was Beregszász ("Berehove" in Ukrainian, Berehovo in Rusyn, Bergsaß in German, Beregovo in Russian, Bereg in Romanian).

The southwestern part remained in Hungary and the county of Szatmár-Ugocsa-Bereg was created in 1923.

After World War II, most of the territory of Bereg county became part of the Soviet Union, Ukrainian SSR, Zakarpattia Oblast.