To provide a steam method in timber drying in which high pressure heating water vapor is fed into a steam atmosphere and the pressurization heating of timber is carried out, when it reaches the fixed pressure, the feeding of the high pressure heating water vapor is suspended and it is made to return to near the ordinary pressure, the timber is dried by repeating these processes for some dozen times.

The steam method in timber drying of this invention is to reduce the water content of timber and dry it by repeating the following processes for some dozen times: a process which feeds water vapor at high temperatures and pressures from a high pressure steam injecting means while pressurizing a timber dry room and interrupts the feeding of water vapor from the above high pressure steam injecting means when it is raised to the specified pressure; and a process which returns the timber dry room to around the ordinary pressure of 1.0 atmospherical pressure.