Abstract: There is provided an indoor unit of an air conditioner, in which a front part of the indoor unit can be easily assembled and disassembled. The indoor unit includes: a main chassis forming a rear appearance; a front frame disposed at a front of the main chassis to form a front appearance; a heat exchanger disposed between the main chassis and the front frame; a fan for generating airflow through the heat exchanger; a suction grill detachably mounted at a front of the front frame; and a filter disposed at a front of the front frame, for filtering foreign particles from air, wherein the suction grill is fixed to the front frame by an elastic deformation.