The merging of silicon microfabrication techniques with surface functionalization biochemistry offers new exciting opportunities in developing microscopic biomedical analysis devices with unique characteristics. Micro-mechanical transducers for chemical and biosensing applications represent one possibility. Microcantilevers can transduce a chemical signal into a mechanical motion with high sensitivity. In this review we summarize how cantilever-based sensors can be operated, and their working principle is presented in few selected biosensing experiments which have been performed recently in our groups in the study of biotin-streptavidin and antigen-antibody interactions, and specific surface charge development of organic molecules. We also discuss the advantages of this novel technique as well as its potentials.