The invention relates to a single-phase high-voltage variable magnetic flux voltage-regulation auto-transformer, and belongs to the manufacturing technical field of a transformer. According to the technical scheme, an iron-core core column (1) is provided with a series winding (4), a common winding (3) and a voltage regulation winding (2) from inside to outside in sequence; an iron-core side column (5) is provided with a third winding (7) and an exciting winding (6) from inside to outside in sequence; the common winding (3) and the voltage regulation winding (2) on the iron-core core column (1) are connected in series, and then connected with the exciting winding (6) on the iron-core side column (5) in parallel; the voltage regulation winding (2) is arranged on a neutral point; and the exciting winding (6) and the constant-voltage common winding (3) are in head-end connection to realize high-voltage variable magnetic flux voltage regulation as well as the constant voltage of the third winding. By adoption of the auto-transformer, the high-voltage variable magnetic flux voltage regulation as well as the constant voltage of the third winding can be realized; and meanwhile, the short-circuit impedance between the winding pairs related to the third winding is greater than 100%, so that the short-circuit endurance capacity of the third winding is improved.