The invention belongs to the field of resource utilization of biomass waste, and particularly relates to a separation method for solid-phase biomass hydrothermal liquefaction products. The solid-phase biomass hydrothermal liquefaction products refer to solid-phase products (comprising oil-phase products and solid residues) obtained by the hydrothermal liquefaction reaction of biomasses, wherein the biomasses comprise enteromorpha, microalgae, rice straws, salix psammophila, tobacco stems, corncobs, sawdust, water hyacinths and the like. According to the method, the solid-phase biomass hydrothermal liquefaction products are mainly used as raw materials, a separation scheme of performing alkali washing and acidification and sequentially and stepwise extracting products by using organic solvents with different polarities is adopted, and the obtained products are analyzed, so that phenol, fatty acid, furan and cyclopentenone compounds can be separated in a way of combining multi-stage solution pH regulation and multi-stage stepwise extraction with the organic solvents with different polarities; the separation method is simple and convenient, environment-friendly, less in pollution, low in cost and favorable for industrial production, and the solvents can be recycled.