Provided is a method for preparing alkali cellulose having alkali distributed uniformly therein. A uniform alkali distribution in the alkali cellulose makes it possible to prepare cellulose ether which has been substituted uniformly in an etherification reaction step. The resulting cellulose ether does not contain a floating water-insoluble portion which will otherwise appear owing to insufficient substitution. More specifically, provided are a method for preparing alkali cellulose, comprising simultaneously feeding pulp powder and an aqueous alkali solution to a high speed disperser to continuously bring them into contact with each other and a method for preparing cellulose ether, comprising reacting the resulting alkali cellulose with an etherifying agent.