Based on symmetrical metalcladding waveguide, the effect of temperature on permittivity of metal layer and refractive index of waveguide layer was studied. By changing the metal permittivity and refractive index of waveguide layer, resonance angle and attenuated total reflection absorption peak were affected. Theory and simulations show that as the temperature rises from 10℃ to 70℃, attenuated total reflection absorption peak decreases and absorption rate improves with increased temperature; resonance angle increases and then decreases with increased temperature on the condition that the wavelength of incident light is 760 nm, the thickness of silver film coverage and silver film substrate is 35 nm and 300 nm, the guiding layer is pure water. When the effect of metal permittivity on the overall is greater than pure water, the resonance angle increases. On the contrary, the resonance angle decreases. Therefore, the temperature effect on the symmetrical metalcladding waveguide can not be ignored.