The present invention relates to a lamp lighting technique for lighting multiple lamps safely without luminance irregularities. The present lamp lighting circuit includes multiple closed loops wherein a predetermined number of lamps and the secondary windings of the predetermined number of transformers are connected serially. At least one of the primary windings of the transformers employed for each closed loop is connected to the primary winding of the transformer employed for another closed loop serially. Thus, current of the lamps included in the closed loop is made uniform, and also current is made uniform even between the closed loops by connecting the primary windings of the transformers serially. According to the present invention, with regard to serial connection of the primary windings of the transformers, even if the number of transformers is limited, current uniformity can be propagated to the entirety by subjecting closed loops to catenation consecutively.