To obtain a hot dip galvanized steel sheet having excellent plating wettability and a galvannealed steel sheet having excellent plating wettability and alloying controllability.

Before a high strength steel sheet is subjected to annealing before plating, fine particles are projected onto its surface. At that time, preferably, the average particle diameter of the fine particles is controlled to 10 to 300 μm, and, as the stock, a metal is used. Further, the fine particles are projected onto the surface of the steel sheet preferably at a projection velocity of 30 to 300 m/s, so as to be a coverage of ≥200%. By projecting the fine particles onto the surface of the steel sheet, a deformed layer is introduced into the surface layer of the steel sheet to a sufficient depth. Then, the deformed layer remains even after annealing, and is, for example, made into the active site of alloying reaction upon alloying treatment, so as to improve the alloying reaction.

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