The present invention provides an organic silicone fine particle for latent electrostatic image developing toners, wherein the organic silicone fine particle has a volume average particle diameter of 0.05 .mu.m to 6.0 .mu.m which is obtained by measurement based on Coulter principle, and has a hemispherical polysiloxane cross-linked structure. By mixing an appropriate amount of an organic silicone resin particle formed in a deformed shape (a hemispherical shape) in a toner or developer, the present invention prevents movement of the organic silicone resin particle from surface functional sites, the movement caused by a phenomenon such as detachment thereof from a toner surface or rolling movement on the toner surface, by the effect of its shape, and makes it possible to effectively achieve the expected function.