© 2016 American Chemical Society.Two experimental methods were developed to determine the solubility of mercury in liquid methane, propane, pentane, octane, and toluene at temperatures from 173 K to 419 K at pressures to 2.1 MPa. For solubility measurements with T > 298 K, a conventional absorption spectroscopic technique at ? = 253.6 nm was used for propane, pentane and octane. Measurements at T <298 K, however, were made using a laser-based technique utilizing two photon excitation at ? = 320.782 nm and subsequent fluorescence detection of the excited electronic state at ? = 546 nm with a photomultiplier. In both methods a literature value for the solubility of mercury in either hexane or toluene at 298 K was used for calibration. The reliability of this new method was verified by comparison of the results referenced with literature data for the solubility of mercury in pentane and octane at T > 298 K. The two-photon technique was also used for measurements on toluene as aromatic hydrocarbons absorb at the 253.6 nm adsorption peak of mercury, the wavelength normally used for mercury analysis. For both methane and propane at T ˜ 175 K the solubility s was ˜1·10-9 mol·dm-3. These values are higher than expected from a generalized plot of log s against 1/T. Values would be expected to be lower than that predicted from the generalized plot as mercury is a solid at T <233 K.