A wavelength-tunable interference filter comprising a first substrate, a second substrate facing the first substrate, a first reflective film provided on the first substrate, a second reflective film provided on the second substrate, the second reflective film facing the first reflective film, a first electrode provided on the first substrate, and a second electrode provided on the second substrate, the second electrode facing the first electrode, wherein the first electrode includes a first electrode layer and a second electrode layer, the first electrode layer has a first in-plane internal stress which is compressive, and the second electrode layer has a second in-plane internal stress which is tensile.