PURPOSE: To prevent noise by providing multi-stage air suction grill in an aspirator provided in the cabin while shifting the grill phase.

CONSTITUTION: An air suction grill for an aspirator is comprised of an air suction outer grill 11 and an inner grill 12 penetrating through an instrument panel 1 and instrument pad 2. Upon driving of an aspirator fan, the air in the cabin will pass through an opening 11b of the outer grill 11 then through an opening 12b of the inner grill 12 to contact against a thermister to function it. Here the noise of fan will pass linearly through said opening 12b as shown by arrow C then collide against the grill 11a. With such arrangement, the noise will detour as shown by arrow D to pass through the opening 11b, resulting in reduction of noise.