To provide an interior switch structure for an automobile, capable of effectively preventing water from invading into a contact part within a switch by a simple structure.

A switch knob 10 is provided, in a reciprocatingly movable manner, having an operation part projecting from the upper surface part of a combination switch body 12. A body structure positioned below the gaps between side-part outer surfaces of the switch knob 10 and outer surfaces of the switch-knob set portion on the upper surface part of the body 12 is formed such that groove parts 30 wider and longer than the gaps cover areas positioned just under the gaps.