The present invention provides dental fillers having the optical and/or mechanical characteristics required to dental materials, a method of producing the same, and a dental composite material prepared with use of the dental filler. More specifically, the present invention provides a dental filler containing a zirconium silicate compound, especially a zirconium trisilicate compound with a wadeite type crystalline structure and having an average particle diameter in the range from 2 to 50,000 nm, a method of producing the same, a dental composite material containing the dental filler and a hardenable resin selected from an acrylic resin, a methacrylic resin, an epoxy resin, a vinyl resin, a urethane resin and the like.