To provide a substrate drier capable of carrying out sufficient drying even to an interior of a small diameter hole.

The substrate drier carries out drying by jetting dry air from a plurality of nozzles 3 arranged on a straight line on a substrate 2 mounted on a moving table 1 moving in one direction, and it is provided with an air supply pipe 5 having the plurality of nozzles arranged perpendicular to the substrate 2 on one track perpendicular to an advancing direction of the substrate 2 at equally spaced pitches, and a linear motor 7 reciprocating the air supply pipe 5. It is more favorable to arrange two sets of the air supply pipes 5 fixed to a needle 7b of the linear motor in parallel with each other, and to drive the two sets in mutually opposite directions.