A new, direct method has been developed to measure the adhesion forces of bovine serum albumin (BSA) on surfaces by using Atomic Force Microscopy (AFM) in liquid environment. We were able to measure interactions between proteins and substrate surface in PBS solution directly without any modification to the substrate or the AFM tip. Two different surfaces have been used in the experiments: mica (hydrophilic surface) and polystyrene (hydrophobic surface). The results show that a polystyrene surface is more adhesive to BSA than a mica surface. This is consistent with previous research, which assessed that hydrophobic surfaces enhance protein adhesion but hydrophilic surfaces do not, demonstrating the effectiveness of the technique.