The renaissance of bio-based materials has been initiated over the last few decades due to limited fossil resources and environmental issues, with global warming, and its effect on climate, being one the most pressing issues. Bio-based polymers represent a wide and highly diverse group of products, where the environmental profile is highly dependent on the used feedstock and thus the it is case specific. Tall oil is a second-generation feedstock. Tall oil is a by-product of coniferous wood recovered in the Kraft (or sulfate method) pulping process. Tall oil fatty acids (TOFA) have been used as a raw material for polyurethane (PU) material production, to do that hydroxyl groups have to be introduced in its chemical structure. TOFA was epoxidized by in situ formed peracetic acid. The molar ratio between C=C/CH3COOH/H2O2 was 1/0.5/1.5. As an acidic catalyst, a catalyst Amberlite IR-120 H as 20% of TOFA mass was used. The epoxy ring-opening reaction was performed with three different polyfunctional alcohols, namely, trimethylolpropane (TMP), triethanolamine (TEOA) and diethylene glycol (DEG). The synthesized tall oil-based polyols were characterized by the hydroxyl (OH) value, acid value, apparent viscosity and moisture content. For a long time the claimed environmental benefits of bio-based materials were not justified. . Life Cycle Assessment (LCA) is a quantitative tool that can be used to assess the environmental performance of biobased products. The aim of this study is to evaluate the cradle-to-gate environmental impact of three different tall oil polyols suitable for rigid PU thermal insulation production. The performed LCA is based on a cradle-to-gate approach, from the production of raw materials to the synthesis of tall oil-based polyols at a pilot-scale reactor (TRL 6). The assessment is based on experimental data from polyol synthesis methods developed at Latvian State Institute of Wood Chemistry.