Provided is an organic silicon compound represented by the following general formula (1) (wherein R1 represents either an alkyl group that has 1 to 20 carbon atoms and may have a substituted group or a cycloalkyl group that has 3 to 20 carbon atoms and may have a substituted group; R2 represents either a hydrogen atom or a monovalent hydrocarbon group that has 1 to 20 carbon atoms and may have a substituted group, and R2 may be either identical or different; and each a independently represents an integer of 1 to 3). The novel silicon-containing compound of the present invention provides a cured product of a room temperature-curable organopolysiloxane composition that is particularly superior in fast curability.