The invention relates to low-iron-loss semi-processed cold-rolled non-oriented electrical steel and a manufacturing method thereof. The manufacturing method includes the steps of performing continuous casting of molten steel to form a sheet billet which is 65-90mm in thickness; placing the sheet billet, without being cooled, into a heating furnace directly for heating at the furnace temperature of 110-1300 DEG C for 0.2-1.5 hours; subjecting the heated sheet billet to hot rolling to manufacture a hot rolled sheet; subjecting the hot rolled sheet to normalizing pickling, cold rolling, cover annealing and flattening to manufacture the finished semi-processed cold-rolled non-oriented electrical steel. The low-iron-loss semi-processed cold-rolled non-oriented electrical steel has the advantages that magnetic performance is quite excellent after stress relieving annealing, a motor made of the electric steel is high in efficiency, and demands of downstream motor users can be satisfied.