The invention provides a fan-shaped section binary lifting system and method of a plate blank continuous casting machine. The system comprises fan-shaped sections, fan-shaped section dowel pins, fan-shaped section replacement guide rails and fan-shaped replacement lifters; multiple fan-shaped section replacement guide rails are provided; the upper parts of the fan-shaped section replacement guiderails are vertical, and the lower parts are distributed in a fan shape; the fan-shaped sections correspond to the fan-shaped section replacement guide rails one to one, and are positioned at the lowerparts of the fan-shaped section replacement guide rails; the fan-shaped section dowel pins are arranged on all the fan-shaped section replacement guide rails; and the lower ends of the fan-shaped replacement lifters are connected with the fan-shaped sections. Under the condition of lower upper limit (limited upper limit) of a traditional continuous casting workshop crown block, the fan-shaped section lifting requirements of a new continuous casting machine after upgrading and transformation of the blank plate continuous casting machine are met. Through a relaying operation mode of fan-shapedsection replacement long and short lifters in the fan-shaped section replacement guide rails, the online replacement and lifting of the fan-shaped sections in the upgraded plate blank continuous casting machine are realized.