A novel alkali-soluble polymer compound including a dehydrogenated pimaric acid and/or its isomer as a repeating unit, and a photosensitive resin composition including the alkali-soluble polymer compound as an effective binder matrix are provided. A photosensitive resin composition using the alkali-soluble polymer compound including a dehydrogenated resin acid has excellent photosensitivity and developing characteristics cause a less deformation in a firing process, has excellent elasticity. Thus, the photosensitive resin composition is advantageous for curing various transparent photosensitive materials, in particular, materials of column spacers, an overcoat, a passivation layer, or the like, used for fabricating color filters of an LCD.