The present invention provides a flexible printed circuit board having a band-like meandering pattern as a whole, which includes multiple linear parts configured about parallel to each other and a folding margin connected to one end in a longitudinal direction of two adjacent linear parts of the multiple linear parts, and which can turn into a single linear product having a total length of not less than 300 mm when the folding margin is double-folded at about a center thereof, and, at the folding margin, either of the two linear parts connected to the folding margin is folded back in a direction opposite by 180 degrees. As a result, a flexible printed circuit board for a catheter, which is sufficiently elongate for use as a signal line of a catheter, can be produced using a general-purpose production apparatus.