To provide a method for preserving mushrooms, capable of inhibiting the quality change of the mushrooms such as Pleurotus comucopiae var. citrinopileatus, P. ostreatus, Lentinula edodes, etc.

The decrease of commercial values caused by the quick quality change after the collection of beautiful mushrooms in growing time is inhibited by using reductive hydrogen water in the step of operations such as harvesting, washing, drying, etc., of the mushrooms so that the reductive hydrogen water acts for the retention of the components held by the mushrooms effectively.