Successful adhesion on wet surfaces is one of the most important challenges in biomedical engineering. Marine fouling organisms exhibit effective adhesion for wet substrates, and the measurement of adhesion forces in wet conditions is the first step toward mimicking the smart strategies of the marine organisms. Surface forces apparatus (SFA) is one of the most powerful nanomechanical tools used to directly measure time- and distance-dependent interactions between biological macromolecules or biological surfaces in an aqueous medium at the molecular level. Recently, SFA has been adapted to probe the biomechanical nature of the underwater adhesive in marine organisms. This review describes some strategies of the marine fouling organisms for successful underwater adhesion determined using SFA.