A controlling method of a wearable electronic apparatus includes: receiving, by an IMU sensor, a bone conduction signal corresponding to vibration in the user's face, while the wearable electronic apparatus is operated in an ANC mode; identifying a presence or an absence of the user's voice based on the bone conduction signal; based on the identifying the presence of the user's voice, controlling an operation mode of the wearable electronic apparatus to be a different operation mode from the ANC mode; while the wearable electronic apparatus is operated in the different operation mode, identifying presence or absence of the user's voice based on the bone conduction signal; and based on the absence of the user's voice being identified for a predetermined time while the wearable electronic apparatus is operated in the different operation mode, controlling the different operation mode to return to the ANC mode.