The present invention relates to a method for easily manufacturing an illumination device in which a surface mount chip-type LED is used, and a wiring board is formed into a truncated conical or another shape. The method includes, in a flexible strip-like wiring board having a partial ring or a linear shape, providing a through-hole T for filling with solder paste S at a wiring end portion L to be connected with a terminal of an LED, temporarily fixing the LED with bond B onto the wiring board held in a plate-like state, filling the through-hole T with the solder paste S from a back surface of the wiring board, rounding the wiring board mounted with the LED into a truncated conical or cylindrical shape, and reflowing the wiring board in the rounded state to solder the LED.