It is an object of the present invention to provide an anchor coating agent that can be used in one layer as an anchor coating for a base material and an inorganic material. An organic-inorganic hybrid coating composition that can be used as the anchor coating agent of the present invention contains the following components. a) an organic silicon compound which is at least one represented by formula (I) RnSiX4-n . . . (I) (wherein R represents an organic group having a carbon atom directly bonded to Si, and X represents a hydroxyl group or a hydrolyzable group; and n represents 1 or 2, wherein when n is 2, each R is the same or different, and when (4-n) is 2, each X is the same or different), wherein a solubility parameter of Rn (SP1) obtained by Fedors' estimation method is smaller than a solubility parameter of an olefin-based polymer (SP2) obtained by Fedors' estimation method and a difference between the SP1 and the SP2 is 1.6 or more (Si1), and/or a condensate thereof; b) a photopolymerization initiator or a thermal polymerization initiator; and c) the olefin-based polymer.