Abstract: There are provided black iron-based particles comprising iron/titanium composite oxide particles having a titanium element content (A) of 5 to 35% by atom based on an iron element content contained in the black iron-based particles, and a ratio of a titanium element content (B) (based on an iron element content contained in the portion dissolved) in a portion of the black iron-based particles, which is dissolved therefrom at an iron element dissolution percentage of 1% by weight, to the titanium content (A) of not less than 1.0. The black iron-based particles of the present invention are not only excellent in dispersibility, acid resistance, tinting strength and blackness, but also exhibit a less magnetization value. Also, the black paint and the rubber or resin composition of the present invention are excellent in acid resistance and blackness.