An optimum evaluation of testicular tissue for diagnostic purposes is only possible by means of the semithin-section-technique, which implies fixation in glutaraldehyde/OsO4 followed by embedding in Epon. Since in clinical departments adequate fixatives are not always available, various storage conditions until further processing were tested. Testicular tissues from 5 men, who underwent orchidectomy, were stored for different periods in solutions of Ringer, 0.9% NaCl, Macrodex, Dextran, 1640 Medium or in a humid chamber either at room temperature or at 4 degrees C, subsequently fixed and then studied by means of light and electron microscopy. Under most conditions, primary spermatocytes and Leydig cells disintegrated rather quickly, while spermatogonia, spermatids and Sertoli cells without fixation were relatively well preserved up to 5 hrs. For optimum preservation the storage of testicular tissue in a humid chamber at 4 degrees C is recommended.