Primary retroperitoneal tumours represent a very uncommon group of neoplasias that account for 0.1%-0.6% of all tumours. Interest in these tumorations arises from the therapeutical and diagnostic concerns they rise. These tumorations are of late diagnosis due to the high insidiousness of their symptoms and, generally, are quite large in size. Widespread use of echography and CAT, however, have increased the possibilities of an occasional asymptomatic diagnosis. Treatment is basically surgical, very much depending on the prognosis of the surgery aggressiveness and the degree of radicality achieved. This paper presents our series of primary retroperitoneal tumours diagnosed between 1978 and 1994.