To provide a dry-distillation pyrolysis device in which a treatment object to be pyrolyzed into dry-distilled gas can be dry-distilled while a vessel storing the treatment object is heated in a shorter time than in the conventional system, and during the above heating process, a second vessel is simultaneously and preliminarily heated with a preheater for an additional time to further reduce the dry-distillation time, and thereby, not only an amount of heavy oil necessary for a burner is reduced but also the time required for dry-distillation of the treatment object in each vessel is reduced to improve the efficiency.

A helical hot air guide passage is disposed in a space between a furnace body and a vessel 9 and/or between the preheater and the second vessel, to enable hot air from the burner to whirl upward around the vessel or the second vessel to heat.