A hairstyling device for curling hair, includes a housing which includes a rolling chamber, an introduction slot which extends over the length of the housing and which opens into the rolling chamber, and an extraction opening arranged on a side end of the housing onto which the rolling chamber opens. The device includes a mandrel which extends into the rolling chamber, and a roller arranged in the rolling chamber and configured to roll the strand of hair around the mandrel, during rotation thereof. The introduction slot includes two walls which extend longitudinally and which cross the thickness of the housing, the side walls including a guiding system configured to promote the penetration of the strand of hair into the rolling chamber.