Angiostrongylus vasorum is an emerging parasite of dogs and related carnivores throughout western Europe and presents a biosecurity threat to many countries worldwide. Infections are difficult to diagnose due to a high variability of clinical signs and can be fatal if left untreated. Previous attempts to develop indirect ELISA as a diagnostic test for antibody presence in dogs have been limited by cross-reactive recognition of antibodies to other endemic nematodes. This study compared the immuno-dominant soluble somatic proteins for first stage, third stage and adult A. vasorum using Western blotting. 2D electrophoresis and mass spectrometry were further used to identify specific immuno-dominant proteins (n = 14) within the soluble fraction from whole adult worms. Proteins included an aspartyl protease inhibitor, representing a potential candidate for a recombinant-based ELISA and novel vaccine.