A scalp monitoring method applied to a smart hair dryer is provided. The method includes obtaining a plurality of head photos by photographing a head of a user using a photographing device. A head region corresponding to each of the plurality of head photos is identified. Once related parameters of each head region is identified based on the head photos corresponding to the each head region, a condition of a scalp of the each head region is analyzed based on the related parameters of the each head region and historical related parameters corresponding to the each head region.