Frederiksborg County (Danish: Frederiksborg Amt) is a former county (Danish: amt) in the north of the island of Zealand in eastern Denmark. Effective January 1, 2007, the county was abolished and merged into Region Hovedstaden (i.e. Copenhagen Capital Region).

55°56′N 12°19′E / 55.933°N 12.317°E / 55.933; 12.317