To provide a printer capable of adjusting temperature and humidity of a printer, and especially capable of seasoning printing paper on standby.

A temperature and humidity adjusting means 16 is equipped with a temperature and humidity control unit 30 capable of supplying set hot air, a blow-off part 31a or 31c connected to the temperature and humidity control unit 30 through an air pipeline, and a detecting sensor 32a or 32c detecting the temperature and humidity of each part of the printer. Arranged outside of a cover CV covering the printer, the temperature and humidity control unit 30 is a means heating, cooling, humidifying and dehumidifying the air, and also a means capable of supplying the air controlled with its temperature and humidity to the inside of the printer. The temperature and humidity inside the printer is adjusted in such a manner that the air is selectively supplied to the blow-off part 31a or 31c from the temperature and humidity control unit 30.