A suspension board with circuit permits a terminal portion to be formed by electrolysis plating without exposing a conductor layer to outside and a production method thereof. After an insulating base layer is formed on a suspension board in a specific pattern in which a second opening is formed, a thin metal film is formed on the insulating base layer and on the suspension board including the second opening exposed from the insulating base layer. A conductor layer is formed in the form of a wired circuit pattern on the thin metal film. An insulating cover layer is formed with a pad opening therein, and a pad portion formed in the pad opening using the suspension board as a lead portion of the electrolysis plating. A first opening larger than the second opening is formed in the suspension board at a portion thereof corresponding to the second opening.