Abstract The complexity of the proteome is extremely high, because every organ or even a part of it can differ considerably in its protein composition. Performing proteomic studies therefore means to separate these functional different tissue areas before analysis. Otherwise all gained results will be depending on the question whether they are incorrect or at least dubious and do they reflect the different functions of tissues at all. The separation of functional tissue areas can be achieved by laser‐based microdissection. In this review we will discuss the compatibly of microdissected formalin or cryofixed tissue with different proteomic techniques like 2‐DE, MS and protein arrays.