Twenty high-boiling hydrophobic solvents were assessed as furfural extraction solvent. 2-sec-Butylphenol with a high furfural partition coefficient, good thermostability, and nonazeotropic property with furfural was chosen as an extraction solvent of furfural for further experimental study. The mutual solubilities for the water2-sec-butylphenol system were measured in the temperature range of (303.15 to 483.15) K at 2.5.10(6) Pa by a static method. The results showed that the solubility data were well correlated with a quadratic equation of temperature. The partition coefficients for furfural and formic acid in the water2-sec-butylphenol system were measured with the same conditions and methods, respectively. The results indicated that the partition coefficient data were temperature dependent and could be well correlated with the vant Hoff equation. This study will have positive influence on further experiments concerning biphasic reaction extraction of furfural and the future industrial production of furfural.