PURPOSE: To obtain a highly precise electromagnetic delay line whose characteristics and delay speed are constant, by laminating preprg layers composed of insulator at least on one surface of a metal plate, forming an inductance by wiring a conuctor convered with insulative resin on the prepreg, and equipping the metal plate and the inductance with terminals.

CONSTITUTION: Prepreg layers 6 composed of insulative resin are laminated on both surfaces of a copper foil 5 being a metal plate. A conductor 7 covered with insulative resin is sent out, made to creep on the prepreg layer 6, bonded, and wired, thereby forming an inductance 8. After that, through holes 9 penetrating the laminated body are formed, and cutting is performed along the lines (a), (b) corresponding to individual electromagnetic delay lines. A lead wire 10 is inserted; the conductors 7 on the front and the rear are soldered, thereby connecting the inductances on the supper and lower surfaces; and next the terminals of the conductors 7 are clamped, and a lead frame 12 is soldered to a specified terminal fixing position and earth electrode leading-out position, thereby forming an electromagnetic delay line 13.