Abstract: A method for the cold sterilization of a tunnel-type oven (1) for the hot sterilization of bottles, having an input chamber (3), a hot sterilization chamber (4), a cooling chamber (5) and a conveyor (6). The method consists of a sequence of operating phases which have to be carried out periodically when the oven is empty. The method includes airtightly closing the input (31) and output (51) openings of the oven (1), suppyling a pre-defined amount of cold sterilization fluid mixed with air, until all the inner surfaces of the oven (1) are reached by the fluid, opening a recycling duct (37); stopping the supply of cold sterilization fluid, and supplying the oven (1) with humidity and temperature controlled air.