An electroless palladium plating liquid, with excellent bath stability, that can provide a film with excellent corrosion resistance, solder bondability, and wire bondability is provided. The invention is an electroless palladium plating liquid, containing: a water soluble palladium compound; at least one of ammonia, an amine compound, an aminocarboxylic acid compound, and carboxylic acid as a complexing agent; and bismuth or a bismuth compound as a stabilizer. Preferably the electroless palladium plating liquid further contains at least one of hypophosphorous acid, phosphorous acid, formic acid, acetic acid, hydrazine, a boron hydride compound, an amine borane compound, and salts thereof as a reducing agent.