The present invention provides a novel dinuclear platinum(II) complex compound that can bind to DNA by a mode different from that of cisplatin-type drugs, a method of producing this compound and an anticancer agent comprising this compound as an effective component. This compound is a tetrazolato-bridged platinum complex compound represented by the following formula (I), wherein A is optionally substituted tetrazolato, B is an inorganic or organic anion, and m and n are integers determined in accordance with the charge number of the platinum complex ion and the charge number of the anion.