A thermosetting resin composition having rubbery polymer particles dispersed therein of the present invention, that does not precipitate the thermosetting resin rubbery polymer particles over a long period of time, has excellent fluidity, is easily cured and molded, and sufficiently exhibits original properties of the thermosetting resin, comprises 100 parts by weight of a thermosetting resin, and 1 to 80 parts by weight of rubbery polymer particles, the rubbery polymer particles being dispersed in the form of a primary particle, wherein the solid content concentration is 60% to 90% by weight, and the water concentration is 3% by weight or less, and can efficiently be produced industrially in the state that the rubbery polymer particles are maintained in a stable state. The composition can be produced by a process for production of a thermosetting resin composition having rubbery polymer particles dispersed therein of the present invention, comprising a concentration step of deaerating a gas phase adjacent to a mixed solution comprising the rubbery polymer particles, the thermosetting resin, water and an organic solvent to reduce the pressure therein, thereby reducing the amounts of the water and the organic solvent in the mixed solution.