An example wearable electronic device includes a housing including a rear cover having a first hole and at least partially contacting a body of a user while the wearable electronic device is worn by the user, a first biometric sensor disposed in the housing and aligned with the first hole, wherein the first biometric sensor includes a first lens disposed in the first hole and is configured to detect first biometric information of the user based on light of a designated wavelength band, which passes through the first lens, a second biometric sensor disposed in the housing and disposed to face the rear cover, wherein the second biometric sensor is configured to detect second biometric information that is different from the first biometric information, and a blocking structure that prevents or reduces foreign substances from being introduced through the first hole.