According to the present invention, an inorganic aggregated particle formed by agglomerating inorganic primary particles having an average particle size of 10 to 1000 nm, and a polymerization monomer that covers the surface of each inorganic primary particle and bonds the inorganic primary particles to each other are cured. In the measurement of the pore volume in which the pore diameter range measured by mercury porosimetry is 1 to 500 nm, the volume of the micropores formed between the organic resin phase is Inorganic agglomerated particles having a macro void with a maximum width of 1 μm or more in the cross section passing through the center of the inorganic agglomerated particles, including an agglomerated gap of 0.01 to 0.30 cm 3 / g, based on 100 measured inorganic particles As an organic-inorganic composite filler having no more than 10, and a method for producing the same.本発明により、平均粒子径１０～１０００ｎｍの無機一次粒子が凝集されてなる無機凝集粒子と、各無機一次粒子の表面を覆うと共に各無機一次粒子を相互に結合する重合性単量体の重合硬化物と、吸水性樹脂とを含む有機樹脂相と、水銀圧入法で測定する孔径範囲が１～５００ｎｍの細孔容積の測定に於いて、有機樹脂相の間に形成されるミクロ孔の容積が０．０１～０．３０ｃｍ３／ｇの凝集間隙とを含み、無機凝集粒子の中心を通る断面内に、最大幅が１μｍ以上のマクロ空隙を有する無機凝集粒子が、測定無機粒子数１００個を基準として、１０個以内である有機無機複合フィラー、及びその製造方法が開示される。
