To provide a vibration insulation mechanism which prevents the deterioration of vibration insulation performance in a precision apparatus.

The vibration insulation mechanism is formed on the bottom of the precision apparatus which is equipped with: an elastic body which attenuates the vibration of the precision apparatus; an upper support which fixes the elastic body in its upper part, has a clearance in which the elastic body oscillates between the elastic body and its side face, and has an upper introduction part on the side face; and a lower support which is fixed to the lower part of the elastic body, has a lower introduction part which guides the elastic body to a constant position by being engaged with the upper introduction part by pressing the precision apparatus in a load direction, and slides on a face on which the precision apparatus is installed by an effect that the elastic body is guided.