A lid lock device includes: a housing including a first housing and a second housing assembled to the first housing and fixed to a vehicle; a lock member movably supported by one or both of the first and second housings and moving between a lock position and a lock releasing position; a surrounding sidewall protruding toward the second housing from the first housing and surrounding a surface of the first housing; a support hole provided in a front side portion of the first housing; a passage port provided in a portion of the surrounding sidewall; a blocking portion protruding toward the first housing from the second housing and blocking the passage port; and an overlapping portion formed in an opening edge of the passage port and overlapping an outer surface of an edge portion of the blocking portion.