To provide a substrate inspecting tool, reducing the contact resistance value between a contact and a connecting electrode part, and having a stable contact resistance value.

This substrate inspecting tool includes: a plurality of contacts; a contact holder having a first guide plate with a first guide hole and a second guide plate with a second guide hole; and the connecting electrode part, wherein the first guide hole is formed to have a smaller diameter than the diameter of an insulating part of the contact, the second guide hole is formed ot have a larger diameter than the diameter of the insulating part of the contact, the first guide plate and the second guide plate have an alignment state where the first guide hole enabling the contact to be attached and detached is aligned with the second guide hole corresponding to the first guide hole and a holding state where the second guide plate holding the contacts is moved in the direction of plane, and the other ends of the contacts and the connecting electrode body come into contact with a part of the opposite connecting electrode part to enter the electrically conducting state.