We have observed DENISP J0255.0-4700 in four mid-infrared photometric passbands at the Gemini South observatory using OSCIR. The photometry indicates that a temperature <=1400 K fits the data reasonably well. This temperature is consistent with previously derived values using optical and near-infrared data and also with our evolutionary parameter estimates of log(L/Lsolar)=-4.62 at a distance of 5 pc and an age of 2-4 Gyr. The implied mass is 60MJ-70MJ. While it is somewhat problematic to fit existing models to the mid-infrared spectrum of DENISP J0255.0-4700, the 10 and 11 μm photometric data appear to be impacted by NH3 absorption. A full spectrum and better models of dwarfs at the L- to T-type transition are required to confirm this.