Organosilicon compound and its production method, compounding agent for rubber, rubber composition, and tire

A method for producing a sulfur-containing organosilicon compound capable of dramatically reducing hysteresis loss of the cured rubber composition and improving abrasion resistance and its production method are provided. A compounding agent for rubber containing the sulfur-containing organosilicon compound, a rubber composition prepared by blending such compounding agent for rubber, and a tire produced by using the cured rubber composition are also provided. The sulfur-containing organosilicon compound has a hydrolyzable silyl group, amino group, and mercapto group.