A high-voltage transformer and method of manufacturing are disclosed. The high-voltage transformer can include a transformer core having at least two core limbs, which are axially parallel and on which in each case a hollow-cylindrical coil having in each case at least one electrical winding is arranged. At least in partial regions of mutually facing surfaces of adjacently arranged coils, the respective surface regions of the coils can have a respective electrically isolating barrier structure, which can be integrated radially on an outside of the coil.