To improve catalytic activity in the production of methylamines in the presence of methanol and ammonia.

In the production of methylamines by reacting methanol with ammonia in the presence of at least one type of a catalyst which is selected from the group consisting of mordenite and clynoptilolite and which has been treated in a liquid phase for silylation using a silylating agent, the temperature of the catalytic layer is maintained at 300 to 400°C for one minute to 10 hours and is subsequently lowered to 200 to 300°C to carry out the reaction.