In an air conditioner having a heat exchanger (5, 116), a drain pan (7, 122) for receiving drain water generated in the heat exchanger, a drain pump (71, 112) for pumping up drain water stocked in the drain pan and discharging the drain water to the outside of the air conditioner and an antibacterial agent unit (110) having a recess portion (90) located below a suction port (71A, 112A) of the drain pump, the antibacterial agent unit is provided with a mount portion (91) around the recess portion, antibacterial agent being filled in the mount portion, a first opening portion (95) through which drain water dropping from the suction port of the drain pump into the recess portion is introduced into the mount portion, and a second opening portion (96) through which the drain water introduced into the mount portion is discharged to the outside of the antibacterial agent unit.