The present invention relates to a hafnium silicide target for forming a gate oxide film composed of HfSi.sub.1.02-2.00. Obtained is a hafnium silicide target superior in workability and embrittlement resistance, and suitable for forming a HfSiO film and HfSiON film that may be used as a high dielectric gate insulation film in substitute for a SiO.sub.2 film, and to the manufacturing method thereof.