To prevent unevenness in drying by controlling a drying speed in real time even when a dried object such as a solvent coating film and a solvent film is dried.

The dried object 12 is dried by applying laser beam to the dried object 12 from a laser irradiation means 14 while longitudinally moving a web of the dried object 12 in drying the web-shaped dried object including a volatile organic solvent as a main component of a solvent, concentration of organic solvent included in a volatile component vaporizing from the dried object 12 is measured by a measuring means 11, and laser output of the laser irradiation means 14 is feedback-controlled to eliminate the difference between the measured value and a predetermined set value.