It is an object of the present invention to provide an electroless gold plating solution capable of directly subjecting a plated coating film made of an underlying metal such as nickel or palladium to gold plate processing, of forming a thick gold plated coating film having a thickness of 0.1 μm or more, of forming a uniform gold plated coating film, and of safely performing plating work. The present invention relates to an electroless gold plating solution comprising: a water-soluble gold compound; and hexahydro-2,4,6-trimethyl-1,3,5-triazine or hexamethylenetetramine. Preferably, the electroless gold plating solution comprises 0.1 to 100 g/L of hexahydro-2,4,6-trimethyl-1,3,5-triazine or hexamethylenetetramine.