We estimate the strength of the bandpass-integrated thermal emission from the extrasolar planet TrES-4 at 3.6, 4.5, 5.8, and 8.0 micron using the Infrared Array Camera (IRAC) on the Spitzer Space Telescope. We find relative eclipse depths of 0.137 +/- 0.011%, 0.148 +/- 0.016%, 0.261 +/- 0.059%, and 0.318 +/- 0.044% in these four bandpasses, respectively. We also place a 2 sigma upper limit of 0.37% on the depth of the secondary eclipse in the 16 micron IRS peak-up array. These eclipse depths reveal that TrES-4 has an emission spectrum similar to that of HD 209458b, which requires the presence of water emission bands created by an thermal inversion layer high in the atmosphere in order to explain the observed features. TrES-4 receives more radiation from its star than HD 209458b and has a correspondingly higher effective temperature, therefore the presence of a temperature inversion in this planets atmosphere lends support to the idea that
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