The preoperative diagnosis of a focal nodular hyperplasia (FNH) is of special interest as in case of non-malignancy of this tumor no extirpation has to be carried out. 86 patients - 19 of them suffered from FNH - have been examined by 3 phasecholescintigraphy. There were no false positive findings (specifity 100 per cent). 2 out of 23 examined FNH were not recognized as such (sensitivity 87 per cent) because the tumor had been changed regressive largely. Cholescintigraphy is an excellent method to prove FNH not bothering the patient too much. Cholescintigraphy should be the first measure of differential diagnostic clarification whenever a benign tumor is suspected.