Recently, there's been a growing trend toward reducing society's carbon footprint. Due to this trend, electric drive mechanisms and electronic control mechanisms have been adopted in products such as automobiles and home electric appliances. One material forming the core of electric drive and electronic control mechanisms is soft magnetic material for alternating current (AC) applications, which is used in electromagnetic conversion components such as motors, transformers and sensors. In this study, the authors have developed the soft magnetic powder core which is made by pressure-forming magnetic powder coated with insulating film. It has high electrical resistance, and therefore exhibits nice electromagnetic conversion characteristics in the high-frequency band. This paper reports on the method of producing the developed core which has both high density and low iron loss.