The present invention relates to a method for manufacturing a flexible printed circuit board and a flexible printed circuit board manufactured thereby, which can secure dimensional stability when sintering a circuit pattern printed with conductive paste by heating a base material to linearly and thermally deform the base material, forming the circuit pattern on one surface of the base material using the conductive paste, and sintering the circuit pattern, and prevents an adhesion reduction between the circuit pattern and the base material due to the film deformation during sintering, and can stably maintain the circuit pattern adhesion even after sintering.