We report a retrospective study about the incidence of second neoplasms (SN) in patients affected by chronic lymphocytic leukemia (CLL) admitted to Padua Hospital between 1989 and 1991, comparing data with those of a similar population. We examined the records of 212 patients, finding in 19 of them 22 second neoplasms; the most common kind was lung cancer. There was an increased incidence of SN, without statistic significance if compared with all sites of cancers in the general population, especially during the first 2 years from the diagnosis of CLL. In accordance with the majority of authors, there is an unknown connection between the two diseases, but certainly independent of chemotherapy with alkylating agents.