Polymethyl methacrylate/epoxy/polymethyl methacrylate (PMMA/epoxy/PMMA) and aluminium/epoxy/aluminium joints were immersed in distilled water and in saline water at different temperatures and subjected to different sinusoidal tensile loads. The joints were also tested in air. The results suggested that the fatigue life of the adhesive joints decreased with increase in the temperature of the solution or load level. Also, PMMA joints showed better fatigue performance both in distilled water and sodium chloride solution than in air, while aluminium joints showed better fatigue performance in air.