Lignin hydrogenolysis has recently been studied extensively as it was shown to result in high monomer yields. Most of these reactions were conducted in liquid solvents, which have shown large impacts on product types and yields. Because adsorption is the first step to any heterogeneous catalyst reactions, this work aims to understand how solvent affects lignin adsorption on Ni(111) and Cu(111) surfaces. To achieve this, density functional theory calculations were employed to investigate β-O-4 lignin dimer (a model compound) adsorption conformations in both vacuum and liquid ethanol. In vacuum, it was found that lignin prefers to adsorb strongly on Ni(111) and weakly on Cu(111) with both aromatic rings parallel to the surface. Solvated adsorption was modeled using both implicit and explicit models. It was found that an explicit model is required to accurately describe the lignin-solvent interactions. With the explicit solvation model, it was predicted that the lignin dimer adsorbs on a Ni(111) surface but not on Cu(111). Furthermore, to circumvent the computationally expensive liquid interface calculations, a thermodynamic cycle method was developed to quickly estimate the solvated lignin dimer adsorption energy from the gas phase adsorption energy and the solvation energies. This model quantifies the effects from the solvent on lignin dimer adsorption, including the contributions from the lignin-solvent and the solvent-metal interactions, and suggests how to design both catalyst and solvent to tune lignin adsorption.